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2024-06-02Merge tag 'x86-urgent-2024-06-02' of ↵Linus Torvalds4-12/+26
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Miscellaneous topology parsing fixes: - Fix topology parsing regression on older CPUs in the new AMD/Hygon parser - Fix boot crash on odd Intel Quark and similar CPUs that do not fill out cpuinfo_x86::x86_clflush_size and zero out cpuinfo_x86::x86_cache_alignment as a result. Provide 32 bytes as a general fallback value. - Fix topology enumeration on certain rare CPUs where the BIOS locks certain CPUID leaves and the kernel unlocked them late, which broke with the new topology parsing code. Factor out this unlocking logic and move it earlier in the parsing sequence" * tag 'x86-urgent-2024-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/topology/intel: Unlock CPUID before evaluating anything x86/cpu: Provide default cache line size if not enumerated x86/topology/amd: Evaluate SMT in CPUID leaf 0x8000001e only on family 0x17 and greater
2024-06-02Merge tag 'sched-urgent-2024-06-02' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fix from Ingo Molnar: "Export a symbol to make life easier for instrumentation/debugging" * tag 'sched-urgent-2024-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/x86: Export 'percpu arch_freq_scale'
2024-06-02Merge tag 'perf-urgent-2024-06-02' of ↵Linus Torvalds3-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf events fix from Ingo Molnar: "Add missing MODULE_DESCRIPTION() lines" * tag 'perf-urgent-2024-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel: Add missing MODULE_DESCRIPTION() lines perf/x86/rapl: Add missing MODULE_DESCRIPTION() line
2024-06-02Merge tag 'powerpc-6.10-2' of ↵Linus Torvalds5-3/+54
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Enforce full ordering for ATOMIC operations with BPF_FETCH - Fix uaccess build errors seen with GCC 13/14 - Fix build errors on ppc32 due to ARCH_HAS_KERNEL_FPU_SUPPORT - Drop error message from lparcfg guest name lookup Thanks to Christophe Leroy, Guenter Roeck, Nathan Lynch, Naveen N Rao, Puranjay Mohan, and Samuel Holland. * tag 'powerpc-6.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc: Limit ARCH_HAS_KERNEL_FPU_SUPPORT to PPC64 powerpc/uaccess: Use YZ asm constraint for ld powerpc/uaccess: Fix build errors seen with GCC 13/14 powerpc/pseries/lparcfg: drop error message from guest name lookup powerpc/bpf: enforce full ordering for ATOMIC operations with BPF_FETCH
2024-05-31Merge tag 'riscv-for-linus-6.10-rc2' of ↵Linus Torvalds4-14/+15
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: - A fix to avoid pt_regs aliasing with idle thread stacks on secondary harts. - HAVE_ARCH_HUGE_VMAP is enabled on XIP kernels, which fixes boot issues on XIP systems with huge pages. - An update to the uABI documentation clarifying that only scalar misaligned accesses were grandfathered in as supported, as the vector extension did not exist at the time the uABI was frozen. - A fix for the recently-added byte/half atomics to avoid losing the fully ordered decorations. * tag 'riscv-for-linus-6.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: Fix fully ordered LR/SC xchg[8|16]() implementations Documentation: RISC-V: uabi: Only scalar misaligned loads are supported riscv: enable HAVE_ARCH_HUGE_VMAP for XIP kernel riscv: prevent pt_regs corruption for secondary idle threads
2024-05-31x86/topology/intel: Unlock CPUID before evaluating anythingThomas Gleixner3-10/+20
Intel CPUs have a MSR bit to limit CPUID enumeration to leaf two. If this bit is set by the BIOS then CPUID evaluation including topology enumeration does not work correctly as the evaluation code does not try to analyze any leaf greater than two. This went unnoticed before because the original topology code just repeated evaluation several times and managed to overwrite the initial limited information with the correct one later. The new evaluation code does it once and therefore ends up with the limited and wrong information. Cure this by unlocking CPUID right before evaluating anything which depends on the maximum CPUID leaf being greater than two instead of rereading stuff after unlock. Fixes: 22d63660c35e ("x86/cpu: Use common topology code for Intel") Reported-by: Peter Schneider <pschneider1968@googlemail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Peter Schneider <pschneider1968@googlemail.com> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/fd3f73dc-a86f-4bcf-9c60-43556a21eb42@googlemail.com
2024-05-31sched/x86: Export 'percpu arch_freq_scale'Phil Auld1-0/+1
Commit: 7bc263840bc3 ("sched/topology: Consolidate and clean up access to a CPU's max compute capacity") removed rq->cpu_capacity_orig in favor of using arch_scale_freq_capacity() calls. Export the underlying percpu symbol on x86 so that external trace point helper modules can be made to work again. Signed-off-by: Phil Auld <pauld@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20240530181548.2039216-1-pauld@redhat.com
2024-05-31perf/x86/intel: Add missing MODULE_DESCRIPTION() linesJeff Johnson2-0/+2
Fix the 'make W=1 C=1' warnings: WARNING: modpost: missing MODULE_DESCRIPTION() in arch/x86/events/intel/intel-uncore.o WARNING: modpost: missing MODULE_DESCRIPTION() in arch/x86/events/intel/intel-cstate.o Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Link: https://lore.kernel.org/r/20240530-md-arch-x86-events-intel-v1-1-8252194ed20a@quicinc.com
2024-05-31perf/x86/rapl: Add missing MODULE_DESCRIPTION() lineJeff Johnson1-0/+1
Fix the warning from 'make C=1 W=1': WARNING: modpost: missing MODULE_DESCRIPTION() in arch/x86/events/rapl.o Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Link: https://lore.kernel.org/r/20240530-md-arch-x86-events-v1-1-e45ffa8af99f@quicinc.com
2024-05-30riscv: Fix fully ordered LR/SC xchg[8|16]() implementationsAlexandre Ghiti1-10/+12
The fully ordered versions of xchg[8|16]() using LR/SC lack the necessary memory barriers to guarantee the order. Fix this by matching what is already implemented in the fully ordered versions of cmpxchg() using LR/SC. Suggested-by: Andrea Parri <parri.andrea@gmail.com> Reported-by: Andrea Parri <parri.andrea@gmail.com> Closes: https://lore.kernel.org/linux-riscv/ZlYbupL5XgzgA0MX@andrea/T/#u Fixes: a8ed2b7a2c13 ("riscv/cmpxchg: Implement xchg for variables of size 1 and 2") Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Andrea Parri <parri.andrea@gmail.com> Link: https://lore.kernel.org/r/20240530145546.394248-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-30riscv: enable HAVE_ARCH_HUGE_VMAP for XIP kernelNam Cao1-1/+1
HAVE_ARCH_HUGE_VMAP also works on XIP kernel, so remove its dependency on !XIP_KERNEL. This also fixes a boot problem for XIP kernel introduced by the commit in "Fixes:". This commit used huge page mapping for vmemmap, but huge page vmap was not enabled for XIP kernel. Fixes: ff172d4818ad ("riscv: Use hugepage mappings for vmemmap") Signed-off-by: Nam Cao <namcao@linutronix.de> Cc: <stable@vger.kernel.org> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240526110104.470429-1-namcao@linutronix.de Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-30riscv: prevent pt_regs corruption for secondary idle threadsSergey Matyukevich2-3/+2
Top of the kernel thread stack should be reserved for pt_regs. However this is not the case for the idle threads of the secondary boot harts. Their stacks overlap with their pt_regs, so both may get corrupted. Similar issue has been fixed for the primary hart, see c7cdd96eca28 ("riscv: prevent stack corruption by reserving task_pt_regs(p) early"). However that fix was not propagated to the secondary harts. The problem has been noticed in some CPU hotplug tests with V enabled. The function smp_callin stored several registers on stack, corrupting top of pt_regs structure including status field. As a result, kernel attempted to save or restore inexistent V context. Fixes: 9a2451f18663 ("RISC-V: Avoid using per cpu array for ordered booting") Fixes: 2875fe056156 ("RISC-V: Add cpu_ops and modify default booting method") Signed-off-by: Sergey Matyukevich <sergey.matyukevich@syntacore.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240523084327.2013211-1-geomatsi@gmail.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-30Merge tag 'net-6.10-rc2' of ↵Linus Torvalds3-16/+18
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from bpf and netfilter. Current release - regressions: - gro: initialize network_offset in network layer - tcp: reduce accepted window in NEW_SYN_RECV state Current release - new code bugs: - eth: mlx5e: do not use ptp structure for tx ts stats when not initialized - eth: ice: check for unregistering correct number of devlink params Previous releases - regressions: - bpf: Allow delete from sockmap/sockhash only if update is allowed - sched: taprio: extend minimum interval restriction to entire cycle too - netfilter: ipset: add list flush to cancel_gc - ipv4: fix address dump when IPv4 is disabled on an interface - sock_map: avoid race between sock_map_close and sk_psock_put - eth: mlx5: use mlx5_ipsec_rx_status_destroy to correctly delete status rules Previous releases - always broken: - core: fix __dst_negative_advice() race - bpf: - fix multi-uprobe PID filtering logic - fix pkt_type override upon netkit pass verdict - netfilter: tproxy: bail out if IP has been disabled on the device - af_unix: annotate data-race around unix_sk(sk)->addr - eth: mlx5e: fix UDP GSO for encapsulated packets - eth: idpf: don't enable NAPI and interrupts prior to allocating Rx buffers - eth: i40e: fully suspend and resume IO operations in EEH case - eth: octeontx2-pf: free send queue buffers incase of leaf to inner - eth: ipvlan: dont Use skb->sk in ipvlan_process_v{4,6}_outbound" * tag 'net-6.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (69 commits) netdev: add qstat for csum complete ipvlan: Dont Use skb->sk in ipvlan_process_v{4,6}_outbound net: ena: Fix redundant device NUMA node override ice: check for unregistering correct number of devlink params ice: fix 200G PHY types to link speed mapping i40e: Fully suspend and resume IO operations in EEH case i40e: factoring out i40e_suspend/i40e_resume e1000e: move force SMBUS near the end of enable_ulp function net: dsa: microchip: fix RGMII error in KSZ DSA driver ipv4: correctly iterate over the target netns in inet_dump_ifaddr() net: fix __dst_negative_advice() race nfc/nci: Add the inconsistency check between the input data length and count MAINTAINERS: dwmac: starfive: update Maintainer net/sched: taprio: extend minimum interval restriction to entire cycle too net/sched: taprio: make q->picos_per_byte available to fill_sched_entry() netfilter: nft_fib: allow from forward/input without iif selector netfilter: tproxy: bail out if IP has been disabled on the device netfilter: nft_payload: skbuff vlan metadata mangle support net: ti: icssg-prueth: Fix start counter for ft1 filter sock_map: avoid race between sock_map_close and sk_psock_put ...
2024-05-30x86/cpu: Provide default cache line size if not enumeratedDave Hansen1-0/+4
tl;dr: CPUs with CPUID.80000008H but without CPUID.01H:EDX[CLFSH] will end up reporting cache_line_size()==0 and bad things happen. Fill in a default on those to avoid the problem. Long Story: The kernel dies a horrible death if c->x86_cache_alignment (aka. cache_line_size() is 0. Normally, this value is populated from c->x86_clflush_size. Right now the code is set up to get c->x86_clflush_size from two places. First, modern CPUs get it from CPUID. Old CPUs that don't have leaf 0x80000008 (or CPUID at all) just get some sane defaults from the kernel in get_cpu_address_sizes(). The vast majority of CPUs that have leaf 0x80000008 also get ->x86_clflush_size from CPUID. But there are oddballs. Intel Quark CPUs[1] and others[2] have leaf 0x80000008 but don't set CPUID.01H:EDX[CLFSH], so they skip over filling in ->x86_clflush_size: cpuid(0x00000001, &tfms, &misc, &junk, &cap0); if (cap0 & (1<<19)) c->x86_clflush_size = ((misc >> 8) & 0xff) * 8; So they: land in get_cpu_address_sizes() and see that CPUID has level 0x80000008 and jump into the side of the if() that does not fill in c->x86_clflush_size. That assigns a 0 to c->x86_cache_alignment, and hilarity ensues in code like: buffer = kzalloc(ALIGN(sizeof(*buffer), cache_line_size()), GFP_KERNEL); To fix this, always provide a sane value for ->x86_clflush_size. Big thanks to Andy Shevchenko for finding and reporting this and also providing a first pass at a fix. But his fix was only partial and only worked on the Quark CPUs. It would not, for instance, have worked on the QEMU config. 1. https://raw.githubusercontent.com/InstLatx64/InstLatx64/master/GenuineIntel/GenuineIntel0000590_Clanton_03_CPUID.txt 2. You can also get this behavior if you use "-cpu 486,+clzero" in QEMU. [ dhansen: remove 'vp_bits_from_cpuid' reference in changelog because bpetkov brutally murdered it recently. ] Fixes: fbf6449f84bf ("x86/sev-es: Set x86_virt_bits to the correct value straight away, instead of a two-phase approach") Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Jörn Heusipp <osmanx@heusipp.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240516173928.3960193-1-andriy.shevchenko@linux.intel.com/ Link: https://lore.kernel.org/lkml/5e31cad3-ad4d-493e-ab07-724cfbfaba44@heusipp.de/ Link: https://lore.kernel.org/all/20240517200534.8EC5F33E%40davehans-spike.ostc.intel.com
2024-05-30x86/topology/amd: Evaluate SMT in CPUID leaf 0x8000001e only on family 0x17 ↵Thomas Gleixner1-2/+2
and greater The new AMD/HYGON topology parser evaluates the SMT information in CPUID leaf 0x8000001e unconditionally while the original code restricted it to CPUs with family 0x17 and greater. This breaks family 0x15 CPUs which advertise that leaf and have a non-zero value in the SMT section. The machine boots, but the scheduler complains loudly about the mismatch of the core IDs: WARNING: CPU: 1 PID: 0 at kernel/sched/core.c:6482 sched_cpu_starting+0x183/0x250 WARNING: CPU: 0 PID: 1 at kernel/sched/topology.c:2408 build_sched_domains+0x76b/0x12b0 Add the condition back to cure it. [ bp: Make it actually build because grandpa is not concerned with trivial stuff. :-P ] Fixes: f7fb3b2dd92c ("x86/cpu: Provide an AMD/HYGON specific topology parser") Closes: https://gitlab.archlinux.org/archlinux/packaging/packages/linux/-/issues/56 Reported-by: Tim Teichmann <teichmanntim@outlook.de> Reported-by: Christian Heusel <christian@heusel.eu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Tim Teichmann <teichmanntim@outlook.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/7skhx6mwe4hxiul64v6azhlxnokheorksqsdbp7qw6g2jduf6c@7b5pvomauugk
2024-05-30powerpc: Limit ARCH_HAS_KERNEL_FPU_SUPPORT to PPC64Samuel Holland1-1/+1
When building a 32-bit kernel, some toolchains do not allow mixing soft float and hard float object files: LD vmlinux.o powerpc64le-unknown-linux-musl-ld: lib/test_fpu_impl.o uses hard float, arch/powerpc/kernel/udbg.o uses soft float powerpc64le-unknown-linux-musl-ld: failed to merge target specific data of file lib/test_fpu_impl.o make[2]: *** [scripts/Makefile.vmlinux_o:62: vmlinux.o] Error 1 make[1]: *** [Makefile:1152: vmlinux_o] Error 2 make: *** [Makefile:240: __sub-make] Error 2 This is not an issue when building a 64-bit kernel. To unbreak the build, limit ARCH_HAS_KERNEL_FPU_SUPPORT to 64-bit kernels. This is okay because the only real user of this option, amdgpu, was previously limited to PPC64 anyway; see commit a28e4b672f04 ("drm/amd/display: use ARCH_HAS_KERNEL_FPU_SUPPORT"). Fixes: 01db473e1aa3 ("powerpc: implement ARCH_HAS_KERNEL_FPU_SUPPORT") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202405250851.Z4daYSWG-lkp@intel.com/ Reported-by: Guenter Roeck <linux@roeck-us.net> Closes: https://lore.kernel.org/lkml/eeffaec3-df63-4e55-ab7a-064a65c00efa@roeck-us.net/ Signed-off-by: Samuel Holland <samuel.holland@sifive.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240529162852.1209-1-samuel.holland@sifive.com
2024-05-30powerpc/uaccess: Use YZ asm constraint for ldMichael Ellerman1-0/+11
The 'ld' instruction requires a 4-byte aligned displacement because it is a DS-form instruction. But the "m" asm constraint doesn't enforce that. Add a special case of __get_user_asm2_goto() so that the "YZ" constraint can be used for "ld". The "Z" constraint is documented in the GCC manual PowerPC machine constraints, and specifies a "memory operand accessed with indexed or indirect addressing". "Y" is not documented in the manual but specifies a "memory operand for a DS-form instruction". Using both allows the compiler to generate a DS-form "ld" or X-form "ldx" as appropriate. The change has to be conditional on CONFIG_PPC_KERNEL_PREFIXED because the "Y" constraint does not guarantee 4-byte alignment when prefixed instructions are enabled. No build errors have been reported due to this, but the possibility is there depending on compiler code generation decisions. Fixes: c20beffeec3c ("powerpc/uaccess: Use flexible addressing with __put_user()/__get_user()") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240529123029.146953-2-mpe@ellerman.id.au
2024-05-30powerpc/uaccess: Fix build errors seen with GCC 13/14Michael Ellerman1-0/+16
Building ppc64le_defconfig with GCC 14 fails with assembler errors: CC fs/readdir.o /tmp/ccdQn0mD.s: Assembler messages: /tmp/ccdQn0mD.s:212: Error: operand out of domain (18 is not a multiple of 4) /tmp/ccdQn0mD.s:226: Error: operand out of domain (18 is not a multiple of 4) ... [6 lines] /tmp/ccdQn0mD.s:1699: Error: operand out of domain (18 is not a multiple of 4) A snippet of the asm shows: # ../fs/readdir.c:210: unsafe_copy_dirent_name(dirent->d_name, name, namlen, efault_end); ld 9,0(29) # MEM[(u64 *)name_38(D) + _88 * 1], MEM[(u64 *)name_38(D) + _88 * 1] # 210 "../fs/readdir.c" 1 1: std 9,18(8) # put_user # *__pus_addr_52, MEM[(u64 *)name_38(D) + _88 * 1] The 'std' instruction requires a 4-byte aligned displacement because it is a DS-form instruction, and as the assembler says, 18 is not a multiple of 4. A similar error is seen with GCC 13 and CONFIG_UBSAN_SIGNED_WRAP=y. The fix is to change the constraint on the memory operand to put_user(), from "m" which is a general memory reference to "YZ". The "Z" constraint is documented in the GCC manual PowerPC machine constraints, and specifies a "memory operand accessed with indexed or indirect addressing". "Y" is not documented in the manual but specifies a "memory operand for a DS-form instruction". Using both allows the compiler to generate a DS-form "std" or X-form "stdx" as appropriate. The change has to be conditional on CONFIG_PPC_KERNEL_PREFIXED because the "Y" constraint does not guarantee 4-byte alignment when prefixed instructions are enabled. Unfortunately clang doesn't support the "Y" constraint so that has to be behind an ifdef. Although the build error is only seen with GCC 13/14, that appears to just be luck. The constraint has been incorrect since it was first added. Fixes: c20beffeec3c ("powerpc/uaccess: Use flexible addressing with __put_user()/__get_user()") Cc: stable@vger.kernel.org # v5.10+ Suggested-by: Kewen Lin <linkw@gcc.gnu.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240529123029.146953-1-mpe@ellerman.id.au
2024-05-30powerpc/pseries/lparcfg: drop error message from guest name lookupNathan Lynch1-2/+2
It's not an error or exceptional situation when the hosting environment does not expose a name for the LP/guest via RTAS or the device tree. This happens with qemu when run without the '-name' option. The message also lacks a newline. Remove it. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Fixes: eddaa9a40275 ("powerpc/pseries: read the lpar name from the firmware") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240524-lparcfg-updates-v2-1-62e2e9d28724@linux.ibm.com
2024-05-29powerpc/bpf: enforce full ordering for ATOMIC operations with BPF_FETCHPuranjay Mohan2-0/+24
The Linux Kernel Memory Model [1][2] requires RMW operations that have a return value to be fully ordered. BPF atomic operations with BPF_FETCH (including BPF_XCHG and BPF_CMPXCHG) return a value back so they need to be JITed to fully ordered operations. POWERPC currently emits relaxed operations for these. We can show this by running the following litmus-test: PPC SB+atomic_add+fetch { 0:r0=x; (* dst reg assuming offset is 0 *) 0:r1=2; (* src reg *) 0:r2=1; 0:r4=y; (* P0 writes to this, P1 reads this *) 0:r5=z; (* P1 writes to this, P0 reads this *) 0:r6=0; 1:r2=1; 1:r4=y; 1:r5=z; } P0 | P1 ; stw r2, 0(r4) | stw r2,0(r5) ; | ; loop:lwarx r3, r6, r0 | ; mr r8, r3 | ; add r3, r3, r1 | sync ; stwcx. r3, r6, r0 | ; bne loop | ; mr r1, r8 | ; | ; lwa r7, 0(r5) | lwa r7,0(r4) ; ~exists(0:r7=0 /\ 1:r7=0) Witnesses Positive: 9 Negative: 3 Condition ~exists (0:r7=0 /\ 1:r7=0) Observation SB+atomic_add+fetch Sometimes 3 9 This test shows that the older store in P0 is reordered with a newer load to a different address. Although there is a RMW operation with fetch between them. Adding a sync before and after RMW fixes the issue: Witnesses Positive: 9 Negative: 0 Condition ~exists (0:r7=0 /\ 1:r7=0) Observation SB+atomic_add+fetch Never 0 9 [1] https://www.kernel.org/doc/Documentation/memory-barriers.txt [2] https://www.kernel.org/doc/Documentation/atomic_t.txt Fixes: aea7ef8a82c0 ("powerpc/bpf/32: add support for BPF_ATOMIC bitwise operations") Fixes: 2d9206b22743 ("powerpc/bpf/32: Add instructions for atomic_[cmp]xchg") Fixes: dbe6e2456fb0 ("powerpc/bpf/64: add support for atomic fetch operations") Fixes: 1e82dfaa7819 ("powerpc/bpf/64: Add instructions for atomic_[cmp]xchg") Cc: stable@vger.kernel.org # v6.0+ Signed-off-by: Puranjay Mohan <puranjay@kernel.org> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Naveen N Rao <naveen@kernel.org> Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240513100248.110535-1-puranjay@kernel.org
2024-05-28Merge tag 'for-netdev' of ↵Jakub Kicinski3-16/+18
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Daniel Borkmann says: ==================== pull-request: bpf 2024-05-27 We've added 15 non-merge commits during the last 7 day(s) which contain a total of 18 files changed, 583 insertions(+), 55 deletions(-). The main changes are: 1) Fix broken BPF multi-uprobe PID filtering logic which filtered by thread while the promise was to filter by process, from Andrii Nakryiko. 2) Fix the recent influx of syzkaller reports to sockmap which triggered a locking rule violation by performing a map_delete, from Jakub Sitnicki. 3) Fixes to netkit driver in particular on skb->pkt_type override upon pass verdict, from Daniel Borkmann. 4) Fix an integer overflow in resolve_btfids which can wrongly trigger build failures, from Friedrich Vock. 5) Follow-up fixes for ARC JIT reported by static analyzers, from Shahab Vahedi. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: selftests/bpf: Cover verifier checks for mutating sockmap/sockhash Revert "bpf, sockmap: Prevent lock inversion deadlock in map delete elem" bpf: Allow delete from sockmap/sockhash only if update is allowed selftests/bpf: Add netkit test for pkt_type selftests/bpf: Add netkit tests for mac address netkit: Fix pkt_type override upon netkit pass verdict netkit: Fix setting mac address in l2 mode ARC, bpf: Fix issues reported by the static analyzers selftests/bpf: extend multi-uprobe tests with USDTs selftests/bpf: extend multi-uprobe tests with child thread case libbpf: detect broken PID filtering logic for multi-uprobe bpf: remove unnecessary rcu_read_{lock,unlock}() in multi-uprobe attach logic bpf: fix multi-uprobe PID filtering logic bpf: Fix potential integer overflow in resolve_btfids MAINTAINERS: Add myself as reviewer of ARM64 BPF JIT ==================== Link: https://lore.kernel.org/r/20240527203551.29712-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-26Merge tag 'mm-hotfixes-stable-2024-05-25-09-13' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "16 hotfixes, 11 of which are cc:stable. A few nilfs2 fixes, the remainder are for MM: a couple of selftests fixes, various singletons fixing various issues in various parts" * tag 'mm-hotfixes-stable-2024-05-25-09-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm/ksm: fix possible UAF of stable_node mm/memory-failure: fix handling of dissolved but not taken off from buddy pages mm: /proc/pid/smaps_rollup: avoid skipping vma after getting mmap_lock again nilfs2: fix potential hang in nilfs_detach_log_writer() nilfs2: fix unexpected freezing of nilfs_segctor_sync() nilfs2: fix use-after-free of timer for log writer thread selftests/mm: fix build warnings on ppc64 arm64: patching: fix handling of execmem addresses selftests/mm: compaction_test: fix bogus test success and reduce probability of OOM-killer invocation selftests/mm: compaction_test: fix incorrect write of zero to nr_hugepages selftests/mm: compaction_test: fix bogus test success on Aarch64 mailmap: update email address for Satya Priya mm/huge_memory: don't unpoison huge_zero_folio kasan, fortify: properly rename memintrinsics lib: add version into /proc/allocinfo output mm/vmalloc: fix vmalloc which may return null if called with __GFP_NOFAIL
2024-05-26Merge tag 'irq-urgent-2024-05-25' of ↵Linus Torvalds1-3/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Ingo Molnar: - Fix x86 IRQ vector leak caused by a CPU offlining race - Fix build failure in the riscv-imsic irqchip driver caused by an API-change semantic conflict - Fix use-after-free in irq_find_at_or_after() * tag 'irq-urgent-2024-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq/irqdesc: Prevent use-after-free in irq_find_at_or_after() genirq/cpuhotplug, x86/vector: Prevent vector leak during CPU offline irqchip/riscv-imsic: Fixup riscv_ipi_set_virq_range() conflict
2024-05-26Merge tag 'x86-urgent-2024-05-25' of ↵Linus Torvalds5-18/+65
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: - Fix regressions of the new x86 CPU VFM (vendor/family/model) enumeration/matching code - Fix crash kernel detection on buggy firmware with non-compliant ACPI MADT tables - Address Kconfig warning * tag 'x86-urgent-2024-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Fix x86_match_cpu() to match just X86_VENDOR_INTEL crypto: x86/aes-xts - switch to new Intel CPU model defines x86/topology: Handle bogus ACPI tables correctly x86/kconfig: Select ARCH_WANT_FRAME_POINTERS again when UNWINDER_FRAME_POINTER=y
2024-05-25Merge tag 'uml-for-linus-6.10-rc1' of ↵Linus Torvalds54-129/+136
git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux Pull UML updates from Richard Weinberger: - Fixes for -Wmissing-prototypes warnings and further cleanup - Remove callback returning void from rtc and virtio drivers - Fix bash location * tag 'uml-for-linus-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux: (26 commits) um: virtio_uml: Convert to platform remove callback returning void um: rtc: Convert to platform remove callback returning void um: Remove unused do_get_thread_area function um: Fix -Wmissing-prototypes warnings for __vdso_* um: Add an internal header shared among the user code um: Fix the declaration of kasan_map_memory um: Fix the -Wmissing-prototypes warning for get_thread_reg um: Fix the -Wmissing-prototypes warning for __switch_mm um: Fix -Wmissing-prototypes warnings for (rt_)sigreturn um: Stop tracking host PID in cpu_tasks um: process: remove unused 'n' variable um: vector: remove unused len variable/calculation um: vector: fix bpfflash parameter evaluation um: slirp: remove set but unused variable 'pid' um: signal: move pid variable where needed um: Makefile: use bash from the environment um: Add winch to winch_handlers before registering winch IRQ um: Fix -Wmissing-prototypes warnings for __warp_* and foo um: Fix -Wmissing-prototypes warnings for text_poke* um: Move declarations to proper headers ...
2024-05-25ARC, bpf: Fix issues reported by the static analyzersShahab Vahedi3-16/+18
Also updated couple of comments along the way. One of the issues reported was indeed a bug in the code: memset(ctx, 0, sizeof(ctx)) // original line memset(ctx, 0, sizeof(*ctx)) // fixed line That was a nice catch. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202405222314.UG5F2NHn-lkp@intel.com/ Closes: https://lore.kernel.org/oe-kbuild-all/202405232036.Xqoc3b0J-lkp@intel.com/ Signed-off-by: Shahab Vahedi <shahab@synopsys.com> Link: https://lore.kernel.org/r/20240525035628.1026-1-list+bpf@vahedi.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-05-24Merge tag 'mm-stable-2024-05-24-11-49' of ↵Linus Torvalds17-1/+18
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more mm updates from Andrew Morton: "Jeff Xu's implementation of the mseal() syscall" * tag 'mm-stable-2024-05-24-11-49' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: selftest mm/mseal read-only elf memory segment mseal: add documentation selftest mm/mseal memory sealing mseal: add mseal syscall mseal: wire up mseal syscall
2024-05-24arm64: patching: fix handling of execmem addressesWill Deacon1-1/+1
Klara Modin reported warnings for a kernel configured with BPF_JIT but without MODULES: [ 44.131296] Trying to vfree() bad address (000000004a17c299) [ 44.138024] WARNING: CPU: 1 PID: 193 at mm/vmalloc.c:3189 remove_vm_area (mm/vmalloc.c:3189 (discriminator 1)) [ 44.146675] CPU: 1 PID: 193 Comm: kworker/1:2 Tainted: G D W 6.9.0-01786-g2c9e5d4a0082 #25 [ 44.158229] Hardware name: Raspberry Pi 3 Model B (DT) [ 44.164433] Workqueue: events bpf_prog_free_deferred [ 44.170492] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 44.178601] pc : remove_vm_area (mm/vmalloc.c:3189 (discriminator 1)) [ 44.183705] lr : remove_vm_area (mm/vmalloc.c:3189 (discriminator 1)) [ 44.188772] sp : ffff800082a13c70 [ 44.193112] x29: ffff800082a13c70 x28: 0000000000000000 x27: 0000000000000000 [ 44.201384] x26: 0000000000000000 x25: ffff00003a44efa0 x24: 00000000d4202000 [ 44.209658] x23: ffff800081223dd0 x22: ffff00003a198a40 x21: ffff8000814dd880 [ 44.217924] x20: 00000000d4202000 x19: ffff8000814dd880 x18: 0000000000000006 [ 44.226206] x17: 0000000000000000 x16: 0000000000000020 x15: 0000000000000002 [ 44.234460] x14: ffff8000811a6370 x13: 0000000020000000 x12: 0000000000000000 [ 44.242710] x11: ffff8000811a6370 x10: 0000000000000144 x9 : ffff8000811fe370 [ 44.250959] x8 : 0000000000017fe8 x7 : 00000000fffff000 x6 : ffff8000811fe370 [ 44.259206] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 [ 44.267457] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff000002203240 [ 44.275703] Call trace: [ 44.279158] remove_vm_area (mm/vmalloc.c:3189 (discriminator 1)) [ 44.283858] vfree (mm/vmalloc.c:3322) [ 44.287835] execmem_free (mm/execmem.c:70) [ 44.292347] bpf_jit_free_exec+0x10/0x1c [ 44.297283] bpf_prog_pack_free (kernel/bpf/core.c:1006) [ 44.302457] bpf_jit_binary_pack_free (kernel/bpf/core.c:1195) [ 44.307951] bpf_jit_free (include/linux/filter.h:1083 arch/arm64/net/bpf_jit_comp.c:2474) [ 44.312342] bpf_prog_free_deferred (kernel/bpf/core.c:2785) [ 44.317785] process_one_work (kernel/workqueue.c:3273) [ 44.322684] worker_thread (kernel/workqueue.c:3342 (discriminator 2) kernel/workqueue.c:3429 (discriminator 2)) [ 44.327292] kthread (kernel/kthread.c:388) [ 44.331342] ret_from_fork (arch/arm64/kernel/entry.S:861) The problem is because bpf_arch_text_copy() silently fails to write to the read-only area as a result of patch_map() faulting and the resulting -EFAULT being chucked away. Update patch_map() to use CONFIG_EXECMEM instead of CONFIG_STRICT_MODULE_RWX to check for vmalloc addresses. Link: https://lkml.kernel.org/r/20240521213813.703309-1-rppt@kernel.org Fixes: 2c9e5d4a0082 ("bpf: remove CONFIG_BPF_JIT dependency on CONFIG_MODULES of") Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Reported-by: Klara Modin <klarasmodin@gmail.com> Closes: https://lore.kernel.org/all/7983fbbf-0127-457c-9394-8d6e4299c685@gmail.com Tested-by: Klara Modin <klarasmodin@gmail.com> Cc: Björn Töpel <bjorn@kernel.org> Cc: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-24Merge tag 'riscv-for-linus-6.10-mw2' of ↵Linus Torvalds20-181/+294
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: - The compression format used for boot images is now configurable at build time, and these formats are shown in `make help` - access_ok() has been optimized - A pair of performance bugs have been fixed in the uaccess handlers - Various fixes and cleanups, including one for the IMSIC build failure and one for the early-boot ftrace illegal NOPs bug * tag 'riscv-for-linus-6.10-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: Fix early ftrace nop patching irqchip: riscv-imsic: Fixup riscv_ipi_set_virq_range() conflict riscv: selftests: Add signal handling vector tests riscv: mm: accelerate pagefault when badaccess riscv: uaccess: Relax the threshold for fast path riscv: uaccess: Allow the last potential unrolled copy riscv: typo in comment for get_f64_reg Use bool value in set_cpu_online() riscv: selftests: Add hwprobe binaries to .gitignore riscv: stacktrace: fixed walk_stackframe() ftrace: riscv: move from REGS to ARGS riscv: do not select MODULE_SECTIONS by default riscv: show help string for riscv-specific targets riscv: make image compression configurable riscv: cpufeature: Fix extension subset checking riscv: cpufeature: Fix thead vector hwcap removal riscv: rewrite __kernel_map_pages() to fix sleeping in invalid context riscv: force PAGE_SIZE linear mapping if debug_pagealloc is enabled riscv: Define TASK_SIZE_MAX for __access_ok() riscv: Remove PGDIR_SIZE_L3 and TASK_SIZE_MIN
2024-05-24Merge tag 'for-linus-6.10a-rc1-tag' of ↵Linus Torvalds2-6/+38
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - a small cleanup in the drivers/xen/xenbus Makefile - a fix of the Xen xenstore driver to improve connecting to a late started Xenstore - an enhancement for better support of ballooning in PVH guests - a cleanup using try_cmpxchg() instead of open coding it * tag 'for-linus-6.10a-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: drivers/xen: Improve the late XenStore init protocol xen/xenbus: Use *-y instead of *-objs in Makefile xen/x86: add extra pages to unpopulated-alloc if available locking/x86/xen: Use try_cmpxchg() in xen_alloc_p2m_entry()
2024-05-24mseal: wire up mseal syscallJeff Xu17-1/+18
Patch series "Introduce mseal", v10. This patchset proposes a new mseal() syscall for the Linux kernel. In a nutshell, mseal() protects the VMAs of a given virtual memory range against modifications, such as changes to their permission bits. Modern CPUs support memory permissions, such as the read/write (RW) and no-execute (NX) bits. Linux has supported NX since the release of kernel version 2.6.8 in August 2004 [1]. The memory permission feature improves the security stance on memory corruption bugs, as an attacker cannot simply write to arbitrary memory and point the code to it. The memory must be marked with the X bit, or else an exception will occur. Internally, the kernel maintains the memory permissions in a data structure called VMA (vm_area_struct). mseal() additionally protects the VMA itself against modifications of the selected seal type. Memory sealing is useful to mitigate memory corruption issues where a corrupted pointer is passed to a memory management system. For example, such an attacker primitive can break control-flow integrity guarantees since read-only memory that is supposed to be trusted can become writable or .text pages can get remapped. Memory sealing can automatically be applied by the runtime loader to seal .text and .rodata pages and applications can additionally seal security critical data at runtime. A similar feature already exists in the XNU kernel with the VM_FLAGS_PERMANENT [3] flag and on OpenBSD with the mimmutable syscall [4]. Also, Chrome wants to adopt this feature for their CFI work [2] and this patchset has been designed to be compatible with the Chrome use case. Two system calls are involved in sealing the map: mmap() and mseal(). The new mseal() is an syscall on 64 bit CPU, and with following signature: int mseal(void addr, size_t len, unsigned long flags) addr/len: memory range. flags: reserved. mseal() blocks following operations for the given memory range. 1> Unmapping, moving to another location, and shrinking the size, via munmap() and mremap(), can leave an empty space, therefore can be replaced with a VMA with a new set of attributes. 2> Moving or expanding a different VMA into the current location, via mremap(). 3> Modifying a VMA via mmap(MAP_FIXED). 4> Size expansion, via mremap(), does not appear to pose any specific risks to sealed VMAs. It is included anyway because the use case is unclear. In any case, users can rely on merging to expand a sealed VMA. 5> mprotect() and pkey_mprotect(). 6> Some destructive madvice() behaviors (e.g. MADV_DONTNEED) for anonymous memory, when users don't have write permission to the memory. Those behaviors can alter region contents by discarding pages, effectively a memset(0) for anonymous memory. The idea that inspired this patch comes from Stephen Röttger’s work in V8 CFI [5]. Chrome browser in ChromeOS will be the first user of this API. Indeed, the Chrome browser has very specific requirements for sealing, which are distinct from those of most applications. For example, in the case of libc, sealing is only applied to read-only (RO) or read-execute (RX) memory segments (such as .text and .RELRO) to prevent them from becoming writable, the lifetime of those mappings are tied to the lifetime of the process. Chrome wants to seal two large address space reservations that are managed by different allocators. The memory is mapped RW- and RWX respectively but write access to it is restricted using pkeys (or in the future ARM permission overlay extensions). The lifetime of those mappings are not tied to the lifetime of the process, therefore, while the memory is sealed, the allocators still need to free or discard the unused memory. For example, with madvise(DONTNEED). However, always allowing madvise(DONTNEED) on this range poses a security risk. For example if a jump instruction crosses a page boundary and the second page gets discarded, it will overwrite the target bytes with zeros and change the control flow. Checking write-permission before the discard operation allows us to control when the operation is valid. In this case, the madvise will only succeed if the executing thread has PKEY write permissions and PKRU changes are protected in software by control-flow integrity. Although the initial version of this patch series is targeting the Chrome browser as its first user, it became evident during upstream discussions that we would also want to ensure that the patch set eventually is a complete solution for memory sealing and compatible with other use cases. The specific scenario currently in mind is glibc's use case of loading and sealing ELF executables. To this end, Stephen is working on a change to glibc to add sealing support to the dynamic linker, which will seal all non-writable segments at startup. Once this work is completed, all applications will be able to automatically benefit from these new protections. In closing, I would like to formally acknowledge the valuable contributions received during the RFC process, which were instrumental in shaping this patch: Jann Horn: raising awareness and providing valuable insights on the destructive madvise operations. Liam R. Howlett: perf optimization. Linus Torvalds: assisting in defining system call signature and scope. Theo de Raadt: sharing the experiences and insight gained from implementing mimmutable() in OpenBSD. MM perf benchmarks ================== This patch adds a loop in the mprotect/munmap/madvise(DONTNEED) to check the VMAs’ sealing flag, so that no partial update can be made, when any segment within the given memory range is sealed. To measure the performance impact of this loop, two tests are developed. [8] The first is measuring the time taken for a particular system call, by using clock_gettime(CLOCK_MONOTONIC). The second is using PERF_COUNT_HW_REF_CPU_CYCLES (exclude user space). Both tests have similar results. The tests have roughly below sequence: for (i = 0; i < 1000, i++) create 1000 mappings (1 page per VMA) start the sampling for (j = 0; j < 1000, j++) mprotect one mapping stop and save the sample delete 1000 mappings calculates all samples. Below tests are performed on Intel(R) Pentium(R) Gold 7505 @ 2.00GHz, 4G memory, Chromebook. Based on the latest upstream code: The first test (measuring time) syscall__ vmas t t_mseal delta_ns per_vma % munmap__ 1 909 944 35 35 104% munmap__ 2 1398 1502 104 52 107% munmap__ 4 2444 2594 149 37 106% munmap__ 8 4029 4323 293 37 107% munmap__ 16 6647 6935 288 18 104% munmap__ 32 11811 12398 587 18 105% mprotect 1 439 465 26 26 106% mprotect 2 1659 1745 86 43 105% mprotect 4 3747 3889 142 36 104% mprotect 8 6755 6969 215 27 103% mprotect 16 13748 14144 396 25 103% mprotect 32 27827 28969 1142 36 104% madvise_ 1 240 262 22 22 109% madvise_ 2 366 442 76 38 121% madvise_ 4 623 751 128 32 121% madvise_ 8 1110 1324 215 27 119% madvise_ 16 2127 2451 324 20 115% madvise_ 32 4109 4642 534 17 113% The second test (measuring cpu cycle) syscall__ vmas cpu cmseal delta_cpu per_vma % munmap__ 1 1790 1890 100 100 106% munmap__ 2 2819 3033 214 107 108% munmap__ 4 4959 5271 312 78 106% munmap__ 8 8262 8745 483 60 106% munmap__ 16 13099 14116 1017 64 108% munmap__ 32 23221 24785 1565 49 107% mprotect 1 906 967 62 62 107% mprotect 2 3019 3203 184 92 106% mprotect 4 6149 6569 420 105 107% mprotect 8 9978 10524 545 68 105% mprotect 16 20448 21427 979 61 105% mprotect 32 40972 42935 1963 61 105% madvise_ 1 434 497 63 63 115% madvise_ 2 752 899 147 74 120% madvise_ 4 1313 1513 200 50 115% madvise_ 8 2271 2627 356 44 116% madvise_ 16 4312 4883 571 36 113% madvise_ 32 8376 9319 943 29 111% Based on the result, for 6.8 kernel, sealing check adds 20-40 nano seconds, or around 50-100 CPU cycles, per VMA. In addition, I applied the sealing to 5.10 kernel: The first test (measuring time) syscall__ vmas t tmseal delta_ns per_vma % munmap__ 1 357 390 33 33 109% munmap__ 2 442 463 21 11 105% munmap__ 4 614 634 20 5 103% munmap__ 8 1017 1137 120 15 112% munmap__ 16 1889 2153 263 16 114% munmap__ 32 4109 4088 -21 -1 99% mprotect 1 235 227 -7 -7 97% mprotect 2 495 464 -30 -15 94% mprotect 4 741 764 24 6 103% mprotect 8 1434 1437 2 0 100% mprotect 16 2958 2991 33 2 101% mprotect 32 6431 6608 177 6 103% madvise_ 1 191 208 16 16 109% madvise_ 2 300 324 24 12 108% madvise_ 4 450 473 23 6 105% madvise_ 8 753 806 53 7 107% madvise_ 16 1467 1592 125 8 108% madvise_ 32 2795 3405 610 19 122% The second test (measuring cpu cycle) syscall__ nbr_vma cpu cmseal delta_cpu per_vma % munmap__ 1 684 715 31 31 105% munmap__ 2 861 898 38 19 104% munmap__ 4 1183 1235 51 13 104% munmap__ 8 1999 2045 46 6 102% munmap__ 16 3839 3816 -23 -1 99% munmap__ 32 7672 7887 216 7 103% mprotect 1 397 443 46 46 112% mprotect 2 738 788 50 25 107% mprotect 4 1221 1256 35 9 103% mprotect 8 2356 2429 72 9 103% mprotect 16 4961 4935 -26 -2 99% mprotect 32 9882 10172 291 9 103% madvise_ 1 351 380 29 29 108% madvise_ 2 565 615 49 25 109% madvise_ 4 872 933 61 15 107% madvise_ 8 1508 1640 132 16 109% madvise_ 16 3078 3323 245 15 108% madvise_ 32 5893 6704 811 25 114% For 5.10 kernel, sealing check adds 0-15 ns in time, or 10-30 CPU cycles, there is even decrease in some cases. It might be interesting to compare 5.10 and 6.8 kernel The first test (measuring time) syscall__ vmas t_5_10 t_6_8 delta_ns per_vma % munmap__ 1 357 909 552 552 254% munmap__ 2 442 1398 956 478 316% munmap__ 4 614 2444 1830 458 398% munmap__ 8 1017 4029 3012 377 396% munmap__ 16 1889 6647 4758 297 352% munmap__ 32 4109 11811 7702 241 287% mprotect 1 235 439 204 204 187% mprotect 2 495 1659 1164 582 335% mprotect 4 741 3747 3006 752 506% mprotect 8 1434 6755 5320 665 471% mprotect 16 2958 13748 10790 674 465% mprotect 32 6431 27827 21397 669 433% madvise_ 1 191 240 49 49 125% madvise_ 2 300 366 67 33 122% madvise_ 4 450 623 173 43 138% madvise_ 8 753 1110 357 45 147% madvise_ 16 1467 2127 660 41 145% madvise_ 32 2795 4109 1314 41 147% The second test (measuring cpu cycle) syscall__ vmas cpu_5_10 c_6_8 delta_cpu per_vma % munmap__ 1 684 1790 1106 1106 262% munmap__ 2 861 2819 1958 979 327% munmap__ 4 1183 4959 3776 944 419% munmap__ 8 1999 8262 6263 783 413% munmap__ 16 3839 13099 9260 579 341% munmap__ 32 7672 23221 15549 486 303% mprotect 1 397 906 509 509 228% mprotect 2 738 3019 2281 1140 409% mprotect 4 1221 6149 4929 1232 504% mprotect 8 2356 9978 7622 953 423% mprotect 16 4961 20448 15487 968 412% mprotect 32 9882 40972 31091 972 415% madvise_ 1 351 434 82 82 123% madvise_ 2 565 752 186 93 133% madvise_ 4 872 1313 442 110 151% madvise_ 8 1508 2271 763 95 151% madvise_ 16 3078 4312 1234 77 140% madvise_ 32 5893 8376 2483 78 142% From 5.10 to 6.8 munmap: added 250-550 ns in time, or 500-1100 in cpu cycle, per vma. mprotect: added 200-750 ns in time, or 500-1200 in cpu cycle, per vma. madvise: added 33-50 ns in time, or 70-110 in cpu cycle, per vma. In comparison to mseal, which adds 20-40 ns or 50-100 CPU cycles, the increase from 5.10 to 6.8 is significantly larger, approximately ten times greater for munmap and mprotect. When I discuss the mm performance with Brian Makin, an engineer who worked on performance, it was brought to my attention that such performance benchmarks, which measuring millions of mm syscall in a tight loop, may not accurately reflect real-world scenarios, such as that of a database service. Also this is tested using a single HW and ChromeOS, the data from another HW or distribution might be different. It might be best to take this data with a grain of salt. This patch (of 5): Wire up mseal syscall for all architectures. Link: https://lkml.kernel.org/r/20240415163527.626541-1-jeffxu@chromium.org Link: https://lkml.kernel.org/r/20240415163527.626541-2-jeffxu@chromium.org Signed-off-by: Jeff Xu <jeffxu@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guenter Roeck <groeck@chromium.org> Cc: Jann Horn <jannh@google.com> [Bug #2] Cc: Jeff Xu <jeffxu@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jorge Lucangeli Obes <jorgelo@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muhammad Usama Anjum <usama.anjum@collabora.com> Cc: Pedro Falcato <pedro.falcato@gmail.com> Cc: Stephen Röttger <sroettger@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Amer Al Shanawany <amer.shanawany@gmail.com> Cc: Javier Carrasco <javier.carrasco.cruz@gmail.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-23genirq/cpuhotplug, x86/vector: Prevent vector leak during CPU offlineDongli Zhang1-3/+6
The absence of IRQD_MOVE_PCNTXT prevents immediate effectiveness of interrupt affinity reconfiguration via procfs. Instead, the change is deferred until the next instance of the interrupt being triggered on the original CPU. When the interrupt next triggers on the original CPU, the new affinity is enforced within __irq_move_irq(). A vector is allocated from the new CPU, but the old vector on the original CPU remains and is not immediately reclaimed. Instead, apicd->move_in_progress is flagged, and the reclaiming process is delayed until the next trigger of the interrupt on the new CPU. Upon the subsequent triggering of the interrupt on the new CPU, irq_complete_move() adds a task to the old CPU's vector_cleanup list if it remains online. Subsequently, the timer on the old CPU iterates over its vector_cleanup list, reclaiming old vectors. However, a rare scenario arises if the old CPU is outgoing before the interrupt triggers again on the new CPU. In that case irq_force_complete_move() is not invoked on the outgoing CPU to reclaim the old apicd->prev_vector because the interrupt isn't currently affine to the outgoing CPU, and irq_needs_fixup() returns false. Even though __vector_schedule_cleanup() is later called on the new CPU, it doesn't reclaim apicd->prev_vector; instead, it simply resets both apicd->move_in_progress and apicd->prev_vector to 0. As a result, the vector remains unreclaimed in vector_matrix, leading to a CPU vector leak. To address this issue, move the invocation of irq_force_complete_move() before the irq_needs_fixup() call to reclaim apicd->prev_vector, if the interrupt is currently or used to be affine to the outgoing CPU. Additionally, reclaim the vector in __vector_schedule_cleanup() as well, following a warning message, although theoretically it should never see apicd->move_in_progress with apicd->prev_cpu pointing to an offline CPU. Fixes: f0383c24b485 ("genirq/cpuhotplug: Add support for cleaning up move in progress") Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240522220218.162423-1-dongli.zhang@oracle.com
2024-05-23Merge tag 'trace-assign-str-v6.10' of ↵Linus Torvalds3-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing cleanup from Steven Rostedt: "Remove second argument of __assign_str() The __assign_str() macro logic of the TRACE_EVENT() macro was optimized so that it no longer needs the second argument. The __assign_str() is always matched with __string() field that takes a field name and the source for that field: __string(field, source) The TRACE_EVENT() macro logic will save off the source value and then use that value to copy into the ring buffer via the __assign_str(). Before commit c1fa617caeb0 ("tracing: Rework __assign_str() and __string() to not duplicate getting the string"), the __assign_str() needed the second argument which would perform the same logic as the __string() source parameter did. Not only would this add overhead, but it was error prone as if the __assign_str() source produced something different, it may not have allocated enough for the string in the ring buffer (as the __string() source was used to determine how much to allocate) Now that the __assign_str() just uses the same string that was used in __string() it no longer needs the source parameter. It can now be removed" * tag 'trace-assign-str-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/treewide: Remove second parameter of __assign_str()
2024-05-23Merge tag 'sparc-for-6.10-tag1' of ↵Linus Torvalds24-114/+76
git://git.kernel.org/pub/scm/linux/kernel/git/alarsson/linux-sparc Pull sparc updates from Andreas Larsson: - Avoid on-stack cpumask variables in a number of places - Move struct termio to asm/termios.h, matching other architectures and allowing certain user space applications to build also for sparc - Fix missing prototype warnings for sparc64 - Fix version generation warnings for sparc32 - Fix bug where non-consecutive CPU IDs lead to some CPUs not starting - Simplification using swap and cleanup using NULL for pointer - Convert sparc parport and chmc drivers to use remove callbacks returning void * tag 'sparc-for-6.10-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/alarsson/linux-sparc: sparc/leon: Remove on-stack cpumask var sparc/pci_msi: Remove on-stack cpumask var sparc/of: Remove on-stack cpumask var sparc/irq: Remove on-stack cpumask var sparc/srmmu: Remove on-stack cpumask var sparc: chmc: Convert to platform remove callback returning void sparc: parport: Convert to platform remove callback returning void sparc: Compare pointers to NULL instead of 0 sparc: Use swap() to fix Coccinelle warning sparc32: Fix version generation failed warnings sparc64: Fix number of online CPUs sparc64: Fix prototype warning for sched_clock sparc64: Fix prototype warnings in adi_64.c sparc64: Fix prototype warning for dma_4v_iotsb_bind sparc64: Fix prototype warning for uprobe_trap sparc64: Fix prototype warning for alloc_irqstack_bootmem sparc64: Fix prototype warning for vmemmap_free sparc64: Fix prototype warnings in traps_64.c sparc64: Fix prototype warning for init_vdso_image sparc: move struct termio to asm/termios.h
2024-05-23Merge tag 'arm64-fixes' of ↵Linus Torvalds10-22/+115
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "The major fix here is for a filesystem corruption issue reported on Apple M1 as a result of buggy management of the floating point register state introduced in 6.8. I initially reverted one of the offending patches, but in the end Ard cooked a proper fix so there's a revert+reapply in the series. Aside from that, we've got some CPU errata workarounds and misc other fixes. - Fix broken FP register state tracking which resulted in filesystem corruption when dm-crypt is used - Workarounds for Arm CPU errata affecting the SSBS Spectre mitigation - Fix lockdep assertion in DMC620 memory controller PMU driver - Fix alignment of BUG table when CONFIG_DEBUG_BUGVERBOSE is disabled" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64/fpsimd: Avoid erroneous elide of user state reload Reapply "arm64: fpsimd: Implement lazy restore for kernel mode FPSIMD" arm64: asm-bug: Add .align 2 to the end of __BUG_ENTRY perf/arm-dmc620: Fix lockdep assert in ->event_init() Revert "arm64: fpsimd: Implement lazy restore for kernel mode FPSIMD" arm64: errata: Add workaround for Arm errata 3194386 and 3312417 arm64: cputype: Add Neoverse-V3 definitions arm64: cputype: Add Cortex-X4 definitions arm64: barrier: Restore spec_bar() macro
2024-05-23Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds1-1/+0
Pull virtio updates from Michael Tsirkin: "Several new features here: - virtio-net is finally supported in vduse - virtio (balloon and mem) interaction with suspend is improved - vhost-scsi now handles signals better/faster And fixes, cleanups all over the place" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (48 commits) virtio-pci: Check if is_avq is NULL virtio: delete vq in vp_find_vqs_msix() when request_irq() fails MAINTAINERS: add Eugenio Pérez as reviewer vhost-vdpa: Remove usage of the deprecated ida_simple_xx() API vp_vdpa: don't allocate unused msix vectors sound: virtio: drop owner assignment fuse: virtio: drop owner assignment scsi: virtio: drop owner assignment rpmsg: virtio: drop owner assignment nvdimm: virtio_pmem: drop owner assignment wifi: mac80211_hwsim: drop owner assignment vsock/virtio: drop owner assignment net: 9p: virtio: drop owner assignment net: virtio: drop owner assignment net: caif: virtio: drop owner assignment misc: nsm: drop owner assignment iommu: virtio: drop owner assignment drm/virtio: drop owner assignment gpio: virtio: drop owner assignment firmware: arm_scmi: virtio: drop owner assignment ...
2024-05-23riscv: Fix early ftrace nop patchingAlexandre Ghiti2-0/+9
Commit c97bf629963e ("riscv: Fix text patching when IPI are used") converted ftrace_make_nop() to use patch_insn_write() which does not emit any icache flush relying entirely on __ftrace_modify_code() to do that. But we missed that ftrace_make_nop() was called very early directly when converting mcount calls into nops (actually on riscv it converts 2B nops emitted by the compiler into 4B nops). This caused crashes on multiple HW as reported by Conor and Björn since the booting core could have half-patched instructions in its icache which would trigger an illegal instruction trap: fix this by emitting a local flush icache when early patching nops. Fixes: c97bf629963e ("riscv: Fix text patching when IPI are used") Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reported-by: Conor Dooley <conor.dooley@microchip.com> Tested-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Tested-by: Björn Töpel <bjorn@rivosinc.com> Link: https://lore.kernel.org/r/20240523115134.70380-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23Merge tag 'mm-nonmm-stable-2024-05-22-17-30' of ↵Linus Torvalds23-12/+180
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more non-mm updates from Andrew Morton: - A series ("kbuild: enable more warnings by default") from Arnd Bergmann which enables a number of additional build-time warnings. We fixed all the fallout which we could find, there may still be a few stragglers. - Samuel Holland has developed the series "Unified cross-architecture kernel-mode FPU API". This does a lot of consolidation of per-architecture kernel-mode FPU usage and enables the use of newer AMD GPUs on RISC-V. - Tao Su has fixed some selftests build warnings in the series "Selftests: Fix compilation warnings due to missing _GNU_SOURCE definition". - This pull also includes a nilfs2 fixup from Ryusuke Konishi. * tag 'mm-nonmm-stable-2024-05-22-17-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (23 commits) nilfs2: make block erasure safe in nilfs_finish_roll_forward() selftests/harness: use 1024 in place of LINE_MAX Revert "selftests/harness: remove use of LINE_MAX" selftests/fpu: allow building on other architectures selftests/fpu: move FP code to a separate translation unit drm/amd/display: use ARCH_HAS_KERNEL_FPU_SUPPORT drm/amd/display: only use hard-float, not altivec on powerpc riscv: add support for kernel-mode FPU x86: implement ARCH_HAS_KERNEL_FPU_SUPPORT powerpc: implement ARCH_HAS_KERNEL_FPU_SUPPORT LoongArch: implement ARCH_HAS_KERNEL_FPU_SUPPORT lib/raid6: use CC_FLAGS_FPU for NEON CFLAGS arm64: crypto: use CC_FLAGS_FPU for NEON CFLAGS arm64: implement ARCH_HAS_KERNEL_FPU_SUPPORT ARM: crypto: use CC_FLAGS_FPU for NEON CFLAGS ARM: implement ARCH_HAS_KERNEL_FPU_SUPPORT arch: add ARCH_HAS_KERNEL_FPU_SUPPORT x86/fpu: fix asm/fpu/types.h include guard kbuild: enable -Wcast-function-type-strict unconditionally kbuild: enable -Wformat-truncation on clang ...
2024-05-23tracing/treewide: Remove second parameter of __assign_str()Steven Rostedt (Google)3-4/+4
With the rework of how the __string() handles dynamic strings where it saves off the source string in field in the helper structure[1], the assignment of that value to the trace event field is stored in the helper value and does not need to be passed in again. This means that with: __string(field, mystring) Which use to be assigned with __assign_str(field, mystring), no longer needs the second parameter and it is unused. With this, __assign_str() will now only get a single parameter. There's over 700 users of __assign_str() and because coccinelle does not handle the TRACE_EVENT() macro I ended up using the following sed script: git grep -l __assign_str | while read a ; do sed -e 's/\(__assign_str([^,]*[^ ,]\) *,[^;]*/\1)/' $a > /tmp/test-file; mv /tmp/test-file $a; done I then searched for __assign_str() that did not end with ';' as those were multi line assignments that the sed script above would fail to catch. Note, the same updates will need to be done for: __assign_str_len() __assign_rel_str() __assign_rel_str_len() I tested this with both an allmodconfig and an allyesconfig (build only for both). [1] https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org/ Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@rorschach.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Christian König <christian.koenig@amd.com> for the amdgpu parts. Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> #for Acked-by: Rafael J. Wysocki <rafael@kernel.org> # for thermal Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Darrick J. Wong <djwong@kernel.org> # xfs Tested-by: Guenter Roeck <linux@roeck-us.net>
2024-05-23Merge patch series "riscv: Extension parsing fixes"Palmer Dabbelt3-7/+45
Charlie Jenkins <charlie@rivosinc.com> says: This series contains two minor fixes for the extension parsing in cpufeature.c. Some T-Head boards without vector 1.0 support report "v" in the isa string in their DT which will cause the kernel to run vector code. The code to blacklist "v" from these boards was doing so by using riscv_cached_mvendorid() which has not been populated at the time of extension parsing. This fix instead greedily reads the mvendorid CSR of the boot hart to determine if the cpu is from T-Head. The other fix is for an incorrect indexing bug. riscv extensions sometimes imply other extensions. When adding these "subset" extensions to the hardware capabilities array, they need to be checked if they are valid. The current code only checks if the extension that is including other extensions is valid and not the subset extensions. These patches were previously included in: https://lore.kernel.org/lkml/20240420-dev-charlie-support_thead_vector_6_9-v3-0-67cff4271d1d@rivosinc.com/ * b4-shazam-merge: riscv: cpufeature: Fix extension subset checking riscv: cpufeature: Fix thead vector hwcap removal Link: https://lore.kernel.org/r/20240502-cpufeature_fixes-v4-0-b3d1a088722d@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23riscv: mm: accelerate pagefault when badaccessKefeng Wang1-2/+2
The access_error() of vma already checked under per-VMA lock, if it is a bad access, directly handle error, no need to retry with mmap_lock again. Since the page faut is handled under per-VMA lock, count it as a vma lock event with VMA_LOCK_SUCCESS. Reviewed-by: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Tested-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240403083805.1818160-6-wangkefeng.wang@huawei.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23riscv: uaccess: Relax the threshold for fast pathXiao Wang1-1/+1
The bytes copy for unaligned head would cover at most SZREG-1 bytes, so it's better to set the threshold as >= (SZREG-1 + word_copy stride size) which equals to 9*SZREG-1. Signed-off-by: Xiao Wang <xiao.w.wang@intel.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240313091929.4029960-1-xiao.w.wang@intel.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23riscv: uaccess: Allow the last potential unrolled copyXiao Wang1-1/+1
When the dst buffer pointer points to the last accessible aligned addr, we could still run another iteration of unrolled copy. Signed-off-by: Xiao Wang <xiao.w.wang@intel.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240313103334.4036554-1-xiao.w.wang@intel.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23riscv: typo in comment for get_f64_regXingyou Chen1-1/+1
Signed-off-by: Xingyou Chen <rockrush@rockwork.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20240317055556.9449-1-rockrush@rockwork.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23Use bool value in set_cpu_online()Zhao Ke1-1/+1
The declaration of set_cpu_online() takes a bool value. So replace int here to make it consistent with the declaration. Signed-off-by: Zhao Ke <ke.zhao@shingroup.cn> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240318065404.123668-1-ke.zhao@shingroup.cn Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23Merge patch series "riscv: fix debug_pagealloc"Palmer Dabbelt2-6/+25
Nam Cao <namcao@linutronix.de> says: The debug_pagealloc feature is not functional on RISCV. With this feature enabled (CONFIG_DEBUG_PAGEALLOC=y and debug_pagealloc=on), kernel crashes early during boot. QEMU command that can reproduce this problem: qemu-system-riscv64 -machine virt \ -kernel Image \ -append "console=ttyS0 root=/dev/vda debug_pagealloc=on" \ -nographic \ -drive "file=root.img,format=raw,id=hd0" \ -device virtio-blk-device,drive=hd0 \ -m 4G \ This series makes debug_pagealloc functional. * b4-shazam-merge: riscv: rewrite __kernel_map_pages() to fix sleeping in invalid context riscv: force PAGE_SIZE linear mapping if debug_pagealloc is enabled Link: https://lore.kernel.org/r/cover.1715750938.git.namcao@linutronix.de Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23riscv: stacktrace: fixed walk_stackframe()Matthew Bystrin1-6/+14
If the load access fault occures in a leaf function (with CONFIG_FRAME_POINTER=y), when wrong stack trace will be displayed: [<ffffffff804853c2>] regmap_mmio_read32le+0xe/0x1c ---[ end trace 0000000000000000 ]--- Registers dump: ra 0xffffffff80485758 <regmap_mmio_read+36> sp 0xffffffc80200b9a0 fp 0xffffffc80200b9b0 pc 0xffffffff804853ba <regmap_mmio_read32le+6> Stack dump: 0xffffffc80200b9a0: 0xffffffc80200b9e0 0xffffffc80200b9e0 0xffffffc80200b9b0: 0xffffffff8116d7e8 0x0000000000000100 0xffffffc80200b9c0: 0xffffffd8055b9400 0xffffffd8055b9400 0xffffffc80200b9d0: 0xffffffc80200b9f0 0xffffffff8047c526 0xffffffc80200b9e0: 0xffffffc80200ba30 0xffffffff8047fe9a The assembler dump of the function preambula: add sp,sp,-16 sd s0,8(sp) add s0,sp,16 In the fist stack frame, where ra is not stored on the stack we can observe: 0(sp) 8(sp) .---------------------------------------------. sp->| frame->fp | frame->ra (saved fp) | |---------------------------------------------| fp->| .... | .... | |---------------------------------------------| | | | and in the code check is performed: if (regs && (regs->epc == pc) && (frame->fp & 0x7)) I see no reason to check frame->fp value at all, because it is can be uninitialized value on the stack. A better way is to check frame->ra to be an address on the stack. After the stacktrace shows as expect: [<ffffffff804853c2>] regmap_mmio_read32le+0xe/0x1c [<ffffffff80485758>] regmap_mmio_read+0x24/0x52 [<ffffffff8047c526>] _regmap_bus_reg_read+0x1a/0x22 [<ffffffff8047fe9a>] _regmap_read+0x5c/0xea [<ffffffff80480376>] _regmap_update_bits+0x76/0xc0 ... ---[ end trace 0000000000000000 ]--- As pointed by Samuel Holland it is incorrect to remove check of the stackframe entirely. Changes since v2 [2]: - Add accidentally forgotten curly brace Changes since v1 [1]: - Instead of just dropping frame->fp check, replace it with validation of frame->ra, which should be a stack address. - Move frame pointer validation into the separate function. [1] https://lore.kernel.org/linux-riscv/20240426072701.6463-1-dev.mbstr@gmail.com/ [2] https://lore.kernel.org/linux-riscv/20240521131314.48895-1-dev.mbstr@gmail.com/ Fixes: f766f77a74f5 ("riscv/stacktrace: Fix stack output without ra on the stack top") Signed-off-by: Matthew Bystrin <dev.mbstr@gmail.com> Reviewed-by: Samuel Holland <samuel.holland@sifive.com> Link: https://lore.kernel.org/r/20240521191727.62012-1-dev.mbstr@gmail.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23ftrace: riscv: move from REGS to ARGSPuranjay Mohan5-141/+143
This commit replaces riscv's support for FTRACE_WITH_REGS with support for FTRACE_WITH_ARGS. This is required for the ongoing effort to stop relying on stop_machine() for RISCV's implementation of ftrace. The main relevant benefit that this change will bring for the above use-case is that now we don't have separate ftrace_caller and ftrace_regs_caller trampolines. This will allow the callsite to call ftrace_caller by modifying a single instruction. Now the callsite can do something similar to: When not tracing: | When tracing: func: func: auipc t0, ftrace_caller_top auipc t0, ftrace_caller_top nop <=========<Enable/Disable>=========> jalr t0, ftrace_caller_bottom [...] [...] The above assumes that we are dropping the support of calling a direct trampoline from the callsite. We need to drop this as the callsite can't change the target address to call, it can only enable/disable a call to a preset target (ftrace_caller in the above diagram). We can later optimize this by calling an intermediate dispatcher trampoline before ftrace_caller. Currently, ftrace_regs_caller saves all CPU registers in the format of struct pt_regs and allows the tracer to modify them. We don't need to save all of the CPU registers because at function entry only a subset of pt_regs is live: |----------+----------+---------------------------------------------| | Register | ABI Name | Description | |----------+----------+---------------------------------------------| | x1 | ra | Return address for traced function | | x2 | sp | Stack pointer | | x5 | t0 | Return address for ftrace_caller trampoline | | x8 | s0/fp | Frame pointer | | x10-11 | a0-1 | Function arguments/return values | | x12-17 | a2-7 | Function arguments | |----------+----------+---------------------------------------------| See RISCV calling convention[1] for the above table. Saving just the live registers decreases the amount of stack space required from 288 Bytes to 112 Bytes. Basic testing was done with this on the VisionFive 2 development board. Note: - Moving from REGS to ARGS will mean that RISCV will stop supporting KPROBES_ON_FTRACE as it requires full pt_regs to be saved. - KPROBES_ON_FTRACE will be supplanted by FPROBES see [2]. [1] https://riscv.org/wp-content/uploads/2015/01/riscv-calling.pdf [2] https://lore.kernel.org/all/170887410337.564249.6360118840946697039.stgit@devnote2/ Signed-off-by: Puranjay Mohan <puranjay@kernel.org> Tested-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Link: https://lore.kernel.org/r/20240405142453.4187-1-puranjay@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23Merge patch series "riscv: access_ok() optimization"Palmer Dabbelt2-4/+1
Samuel Holland <samuel.holland@sifive.com> says: This series optimizes access_ok() by defining TASK_SIZE_MAX. At Alex's suggestion, I also tried making TASK_SIZE constant (specifically by making PGDIR_SHIFT a variable instead of a ternary expression, then replacing the load with an immediate using ALTERNATIVE). This appeared to slightly improve performance on some implementations (C906) but regressed it on others (FU740). So I am leaving further optimizations to a later series. * b4-shazam-merge: riscv: Define TASK_SIZE_MAX for __access_ok() riscv: Remove PGDIR_SIZE_L3 and TASK_SIZE_MIN Link: https://lore.kernel.org/r/20240327143858.711792-1-samuel.holland@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-23riscv: do not select MODULE_SECTIONS by defaultQingfang Deng1-1/+1
Since commit aad15bc85c18 ("riscv: Change code model of module to medany to improve data accessing"), kernel modules have not been built with -fPIC, so they wouldn't have R_RISCV_GOT_HI20 or R_RISCV_CALL_PLT relocations, and handling of those relocations is unnecessary. If RELOCATABLE=y, kernel modules will be built with -fPIE, which would reintroduce said relocations, so only select MODULE_SECTIONS when RELOCATABLE. Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240511015725.1162-1-dqfext@gmail.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>