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2021-10-07powerpc/64: warn if local irqs are enabled in NMI or hardirq contextNicholas Piggin1-0/+6
This can help catch bugs such as the one fixed by the previous change to prevent _exception() from enabling irqs. ppc32 could have a similar warning but it has no good config option to debug this stuff (the test may be overkill to add for production kernels). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211004145642.1331214-4-npiggin@gmail.com
2021-08-12powerpc/interrupt: Fix OOPS by not calling do_IRQ() from timer_interrupt()Christophe Leroy1-1/+6
An interrupt handler shall not be called from another interrupt handler otherwise this leads to problems like the following: Kernel attempted to write user page (afd4fa84) - exploit attempt? (uid: 1000) ------------[ cut here ]------------ Bug: Write fault blocked by KUAP! WARNING: CPU: 0 PID: 1617 at arch/powerpc/mm/fault.c:230 do_page_fault+0x484/0x720 Modules linked in: CPU: 0 PID: 1617 Comm: sshd Tainted: G W 5.13.0-pmac-00010-g8393422eb77 #7 NIP: c001b77c LR: c001b77c CTR: 00000000 REGS: cb9e5bc0 TRAP: 0700 Tainted: G W (5.13.0-pmac-00010-g8393422eb77) MSR: 00021032 <ME,IR,DR,RI> CR: 24942424 XER: 00000000 GPR00: c001b77c cb9e5c80 c1582c00 00000021 3ffffbff 085b0000 00000027 c8eb644c GPR08: 00000023 00000000 00000000 00000000 24942424 0063f8c8 00000000 000186a0 GPR16: afd52dd4 afd52dd0 afd52dcc afd52dc8 0065a990 c07640c4 cb9e5e98 cb9e5e90 GPR24: 00000040 afd4fa96 00000040 02000000 c1fda6c0 afd4fa84 00000300 cb9e5cc0 NIP [c001b77c] do_page_fault+0x484/0x720 LR [c001b77c] do_page_fault+0x484/0x720 Call Trace: [cb9e5c80] [c001b77c] do_page_fault+0x484/0x720 (unreliable) [cb9e5cb0] [c000424c] DataAccess_virt+0xd4/0xe4 --- interrupt: 300 at __copy_tofrom_user+0x110/0x20c NIP: c001f9b4 LR: c03250a0 CTR: 00000004 REGS: cb9e5cc0 TRAP: 0300 Tainted: G W (5.13.0-pmac-00010-g8393422eb77) MSR: 00009032 <EE,ME,IR,DR,RI> CR: 48028468 XER: 20000000 DAR: afd4fa84 DSISR: 0a000000 GPR00: 20726f6f cb9e5d80 c1582c00 00000004 cb9e5e3a 00000016 afd4fa80 00000000 GPR08: 3835202d 72777872 2d78722d 00000004 28028464 0063f8c8 00000000 000186a0 GPR16: afd52dd4 afd52dd0 afd52dcc afd52dc8 0065a990 c07640c4 cb9e5e98 cb9e5e90 GPR24: 00000040 afd4fa96 00000040 cb9e5e0c 00000daa a0000000 cb9e5e98 afd4fa56 NIP [c001f9b4] __copy_tofrom_user+0x110/0x20c LR [c03250a0] _copy_to_iter+0x144/0x990 --- interrupt: 300 [cb9e5d80] [c03e89c0] n_tty_read+0xa4/0x598 (unreliable) [cb9e5df0] [c03e2a0c] tty_read+0xdc/0x2b4 [cb9e5e80] [c0156bf8] vfs_read+0x274/0x340 [cb9e5f00] [c01571ac] ksys_read+0x70/0x118 [cb9e5f30] [c0016048] ret_from_syscall+0x0/0x28 --- interrupt: c00 at 0xa7855c88 NIP: a7855c88 LR: a7855c5c CTR: 00000000 REGS: cb9e5f40 TRAP: 0c00 Tainted: G W (5.13.0-pmac-00010-g8393422eb77) MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 2402446c XER: 00000000 GPR00: 00000003 afd4ec70 a72137d0 0000000b afd4ecac 00004000 0065a990 00000800 GPR08: 00000000 a7947930 00000000 00000004 c15831b0 0063f8c8 00000000 000186a0 GPR16: afd52dd4 afd52dd0 afd52dcc afd52dc8 0065a990 0065a9e0 00000001 0065fac0 GPR24: 00000000 00000089 00664050 00000000 00668e30 a720c8dc a7943ff4 0065f9b0 NIP [a7855c88] 0xa7855c88 LR [a7855c5c] 0xa7855c5c --- interrupt: c00 Instruction dump: 3884aa88 38630178 48076861 807f0080 48042e45 2f830000 419e0148 3c80c079 3c60c076 38841be4 386301c0 4801f705 <0fe00000> 3860000b 4bfffe30 3c80c06b ---[ end trace fd69b91a8046c2e5 ]--- Here the problem is that by re-enterring an exception handler, kuap_save_and_lock() is called a second time with this time KUAP access locked, leading to regs->kuap being overwritten hence KUAP not being unlocked at exception exit as expected. Do not call do_IRQ() from timer_interrupt() directly. Instead, redefine do_IRQ() as a standard function named __do_IRQ(), and call it from both do_IRQ() and time_interrupt() handlers. Fixes: 3a96570ffceb ("powerpc: convert interrupt handlers to use wrappers") Cc: stable@vger.kernel.org # v5.12+ Reported-by: Stan Johnson <userm57@yahoo.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c17d234f4927d39a1d7100864a8e1145323d33a0.1628611927.git.christophe.leroy@csgroup.eu
2021-06-30powerpc/64: enable MSR[EE] in irq replay pt_regsNicholas Piggin1-0/+1
Similar to commit 2b48e96be2f9f ("powerpc/64: fix irq replay pt_regs->softe value"), enable MSR_EE in pt_regs->msr. This makes the regs look more normal. It also allows some extra debug checks to be added to interrupt handler entry. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210630074621.2109197-7-npiggin@gmail.com
2021-06-24powerpc/64: interrupt soft-enable race fixNicholas Piggin1-0/+95
Prevent interrupt restore from allowing racing hard interrupts going ahead of previous soft-pending ones, by using the soft-masked restart handler to allow a store to clear the soft-mask while knowing nothing is soft-pending. This probably doesn't matter much in practice, but it's a simple demonstrator / test case to exercise the restart table logic. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-11-npiggin@gmail.com
2021-04-21powerpc/irq: Enhance readability of trap typesChristophe Leroy1-8/+5
This patch makes use of trap types in irq.c Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/f7f8c9f98c33eaea316755c7fef150d1d77e047d.1618847273.git.christophe.leroy@csgroup.eu
2021-04-14powerpc/64e/interrupt: use new interrupt returnNicholas Piggin1-76/+0
Update the new C and asm interrupt return code to account for 64e specifics, switch over to use it. The now-unused old ret_from_except code, that was moved to 64e after the 64s conversion, is removed. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210316104206.407354-5-npiggin@gmail.com
2021-03-29powerpc/irq: Inline call_do_irq() and call_do_softirq()Christophe Leroy1-0/+41
call_do_irq() and call_do_softirq() are simple enough to be worth inlining. Inlining them avoids an mflr/mtlr pair plus a save/reload on stack. This is inspired from S390 arch. Several other arches do more or less the same. The way sparc arch does seems odd thought. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210320122227.345427-1-mpe@ellerman.id.au
2021-03-29powerpc/64s: Make kuap_check_amr() and kuap_get_and_check_amr() genericChristophe Leroy1-1/+1
In preparation of porting powerpc32 to C syscall entry/exit, rename kuap_check_amr() and kuap_get_and_check_amr() as kuap_assert_locked() and kuap_get_and_assert_locked(), and move in the generic asm/kup.h the stub for when CONFIG_PPC_KUAP is not selected. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/f82614d9b17b83abd739aa18fc08811815d0c2e3.1615552867.git.christophe.leroy@csgroup.eu
2021-02-25Merge tag 'x86-entry-2021-02-24' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 irq entry updates from Thomas Gleixner: "The irq stack switching was moved out of the ASM entry code in course of the entry code consolidation. It ended up being suboptimal in various ways. This reworks the X86 irq stack handling: - Make the stack switching inline so the stackpointer manipulation is not longer at an easy to find place. - Get rid of the unnecessary indirect call. - Avoid the double stack switching in interrupt return and reuse the interrupt stack for softirq handling. - A objtool fix for CONFIG_FRAME_POINTER=y builds where it got confused about the stack pointer manipulation" * tag 'x86-entry-2021-02-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool: Fix stack-swizzle for FRAME_POINTER=y um: Enforce the usage of asm-generic/softirq_stack.h x86/softirq/64: Inline do_softirq_own_stack() softirq: Move do_softirq_own_stack() to generic asm header softirq: Move __ARCH_HAS_DO_SOFTIRQ to Kconfig x86: Select CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK x86/softirq: Remove indirection in do_softirq_own_stack() x86/entry: Use run_sysvec_on_irqstack_cond() for XEN upcall x86/entry: Convert device interrupts to inline stack switching x86/entry: Convert system vectors to irq stack macro x86/irq: Provide macro for inlining irq stack switching x86/apic: Split out spurious handling code x86/irq/64: Adjust the per CPU irq stack pointer by 8 x86/irq: Sanitize irq stack tracking x86/entry: Fix instrumentation annotation
2021-02-23Merge tag 'powerpc-5.12-1' of ↵Linus Torvalds1-6/+28
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - A large series adding wrappers for our interrupt handlers, so that irq/nmi/user tracking can be isolated in the wrappers rather than spread in each handler. - Conversion of the 32-bit syscall handling into C. - A series from Nick to streamline our TLB flushing when using the Radix MMU. - Switch to using queued spinlocks by default for 64-bit server CPUs. - A rework of our PCI probing so that it happens later in boot, when more generic infrastructure is available. - Two small fixes to allow 32-bit little-endian processes to run on 64-bit kernels. - Other smaller features, fixes & cleanups. Thanks to: Alexey Kardashevskiy, Ananth N Mavinakayanahalli, Aneesh Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Cédric Le Goater, Chengyang Fan, Christophe Leroy, Christopher M. Riedl, Fabiano Rosas, Florian Fainelli, Frederic Barrat, Ganesh Goudar, Hari Bathini, Jiapeng Chong, Joseph J Allen, Kajol Jain, Markus Elfring, Michal Suchanek, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Pingfan Liu, Po-Hsu Lin, Qian Cai, Ram Pai, Randy Dunlap, Sandipan Das, Stephen Rothwell, Tyrel Datwyler, Will Springer, Yury Norov, and Zheng Yongjun. * tag 'powerpc-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (188 commits) powerpc/perf: Adds support for programming of Thresholding in P10 powerpc/pci: Remove unimplemented prototypes powerpc/uaccess: Merge raw_copy_to_user_allowed() into raw_copy_to_user() powerpc/uaccess: Merge __put_user_size_allowed() into __put_user_size() powerpc/uaccess: get rid of small constant size cases in raw_copy_{to,from}_user() powerpc/64: Fix stack trace not displaying final frame powerpc/time: Remove get_tbl() powerpc/time: Avoid using get_tbl() spi: mpc52xx: Avoid using get_tbl() powerpc/syscall: Avoid storing 'current' in another pointer powerpc/32: Handle bookE debugging in C in syscall entry/exit powerpc/syscall: Do not check unsupported scv vector on PPC32 powerpc/32: Remove the counter in global_dbcr0 powerpc/32: Remove verification of MSR_PR on syscall in the ASM entry powerpc/syscall: implement system call entry/exit logic in C for PPC32 powerpc/32: Always save non volatile GPRs at syscall entry powerpc/syscall: Change condition to check MSR_RI powerpc/syscall: Save r3 in regs->orig_r3 powerpc/syscall: Use is_compat_task() powerpc/syscall: Make interrupt.c buildable on PPC32 ...
2021-02-12Merge branch 'x86/paravirt' into x86/entryIngo Molnar1-12/+16
Merge in the recent paravirt changes to resolve conflicts caused by objtool annotations. Conflicts: arch/x86/xen/xen-asm.S Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-02-11powerpc/kuap: Restore AMR after replaying soft interruptsAlexey Kardashevskiy1-1/+26
Since de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection"), user access helpers call user_{read|write}_access_{begin|end} when user space access is allowed. Commit 890274c2dc4c ("powerpc/64s: Implement KUAP for Radix MMU") made the mentioned helpers program a AMR special register to allow such access for a short period of time, most of the time AMR is expected to block user memory access by the kernel. Since the code accesses the user space memory, unsafe_get_user() calls might_fault() which calls arch_local_irq_restore() if either CONFIG_PROVE_LOCKING or CONFIG_DEBUG_ATOMIC_SLEEP is enabled. arch_local_irq_restore() then attempts to replay pending soft interrupts as KUAP regions have hardware interrupts enabled. If a pending interrupt happens to do user access (performance interrupts do that), it enables access for a short period of time so after returning from the replay, the user access state remains blocked and if a user page fault happens - "Bug: Read fault blocked by AMR!" appears and SIGSEGV is sent. An example trace: Bug: Read fault blocked by AMR! WARNING: CPU: 0 PID: 1603 at /home/aik/p/kernel/arch/powerpc/include/asm/book3s/64/kup-radix.h:145 CPU: 0 PID: 1603 Comm: amr Not tainted 5.10.0-rc6_v5.10-rc6_a+fstn1 #24 NIP: c00000000009ece8 LR: c00000000009ece4 CTR: 0000000000000000 REGS: c00000000dc63560 TRAP: 0700 Not tainted (5.10.0-rc6_v5.10-rc6_a+fstn1) MSR: 8000000000021033 <SF,ME,IR,DR,RI,LE> CR: 28002888 XER: 20040000 CFAR: c0000000001fa928 IRQMASK: 1 GPR00: c00000000009ece4 c00000000dc637f0 c000000002397600 000000000000001f GPR04: c0000000020eb318 0000000000000000 c00000000dc63494 0000000000000027 GPR08: c00000007fe4de68 c00000000dfe9180 0000000000000000 0000000000000001 GPR12: 0000000000002000 c0000000030a0000 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 bfffffffffffffff GPR20: 0000000000000000 c0000000134a4020 c0000000019c2218 0000000000000fe0 GPR24: 0000000000000000 0000000000000000 c00000000d106200 0000000040000000 GPR28: 0000000000000000 0000000000000300 c00000000dc63910 c000000001946730 NIP __do_page_fault+0xb38/0xde0 LR __do_page_fault+0xb34/0xde0 Call Trace: __do_page_fault+0xb34/0xde0 (unreliable) handle_page_fault+0x10/0x2c --- interrupt: 300 at strncpy_from_user+0x290/0x440 LR = strncpy_from_user+0x284/0x440 strncpy_from_user+0x2f0/0x440 (unreliable) getname_flags+0x88/0x2c0 do_sys_openat2+0x2d4/0x5f0 do_sys_open+0xcc/0x140 system_call_exception+0x160/0x240 system_call_common+0xf0/0x27c To fix it save/restore the AMR when replaying interrupts, and also add a check if AMR was not blocked prior to replaying interrupts. Originally found by syzkaller. Fixes: 890274c2dc4c ("powerpc/64s: Implement KUAP for Radix MMU") Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Use normal commit citation format and add full oops log to change log, move kuap_check_amr() into the restore routine to avoid warnings about unreconciled IRQ state] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210202091541.36499-1-aik@ozlabs.ru
2021-02-11softirq: Move do_softirq_own_stack() to generic asm headerThomas Gleixner1-0/+1
To avoid include recursion hell move the do_softirq_own_stack() related content into a generic asm header and include it from all places in arch/ which need the prototype. This allows architectures to provide an inline implementation of do_softirq_own_stack() without introducing a lot of #ifdeffery all over the place. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002513.289960691@linutronix.de
2021-02-08powerpc: handle irq_enter/irq_exit in interrupt handler wrappersNicholas Piggin1-4/+0
Move irq_enter/irq_exit into asynchronous interrupt handler wrappers. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210130130852.2952424-35-npiggin@gmail.com
2021-02-08powerpc: convert interrupt handlers to use wrappersNicholas Piggin1-1/+2
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210130130852.2952424-29-npiggin@gmail.com
2021-01-24powerpc/64s: prevent recursive replay_soft_interrupts causing superfluous ↵Nicholas Piggin1-12/+16
interrupt When an asynchronous interrupt calls irq_exit, it checks for softirqs that may have been created, and runs them. Running softirqs enables local irqs, which can replay pending interrupts causing recursion in replay_soft_interrupts. This abridged trace shows how this can occur: ! NIP replay_soft_interrupts LR interrupt_exit_kernel_prepare Call Trace: interrupt_exit_kernel_prepare (unreliable) interrupt_return --- interrupt: ea0 at __rb_reserve_next NIP __rb_reserve_next LR __rb_reserve_next Call Trace: ring_buffer_lock_reserve trace_function function_trace_call ftrace_call __do_softirq irq_exit timer_interrupt ! replay_soft_interrupts interrupt_exit_kernel_prepare interrupt_return --- interrupt: ea0 at arch_local_irq_restore This can not be prevented easily, because softirqs must not block hard irqs, so it has to be dealt with. The recursion is bounded by design in the softirq code because softirq replay disables softirqs and loops around again to check for new softirqs created while it ran, so that's not a problem. However it does mess up interrupt replay state, causing superfluous interrupts when the second replay_soft_interrupts clears a pending interrupt, leaving it still set in the first call in the 'happened' local variable. Fix this by not caching a copy of irqs_happened across interrupt handler calls. Fixes: 3282a3da25bd ("powerpc/64: Implement soft interrupt replay in C") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210123061244.2076145-1-npiggin@gmail.com
2020-12-09powerpc/64: irq replay remove decrementer overflow checkNicholas Piggin1-49/+4
This is way to catch some cases of decrementer overflow, when the decrementer has underflowed an odd number of times, while MSR[EE] was disabled. With a typical small decrementer, a timer that fires when MSR[EE] is disabled will be "lost" if MSR[EE] remains disabled for between 4.3 and 8.6 seconds after the timer expires. In any case, the decrementer interrupt would be taken at 8.6 seconds and the timer would be found at that point. So this check is for catching extreme latency events, and it prevents those latencies from being a further few seconds long. It's not obvious this is a good tradeoff. This is already a watchdog magnitude event and that situation is not improved a significantly with this check. For large decrementers, it's useless. Therefore remove this check, which avoids a mftb when enabling hard disabled interrupts (e.g., when enabling after coming from hardware interrupt handlers). Perhaps more importantly, it also removes the clunky MSR[EE] vs PACA_IRQ_HARD_DIS incoherency in soft-interrupt replay which simplifies the code. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201107014336.2337337-1-npiggin@gmail.com
2020-10-08powerpc: Remove get_tb_or_rtc()Christophe Leroy1-1/+1
601 is gone, get_tb_or_rtc() is equivalent to get_tb(). Replace the former by the later. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/3e8a13ee83418630c753c30cb722ae682d5b2d39.1601362098.git.christophe.leroy@csgroup.eu
2020-10-06powerpc/64: make restore_interrupts 64e onlyNicholas Piggin1-18/+19
This is not used by 64s. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200915114650.3980244-5-npiggin@gmail.com
2020-10-06powerpc/64e: remove 64s specific interrupt soft-mask codeNicholas Piggin1-1/+1
Since the assembly soft-masking code was moved to 64e specific, there are some 64s specific interrupt types still there. Remove them. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200915114650.3980244-4-npiggin@gmail.com
2020-10-06powerpc/64e: remove PACA_IRQ_EE_EDGENicholas Piggin1-23/+0
This is not used anywhere. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200915114650.3980244-3-npiggin@gmail.com
2020-10-06powerpc/64: fix irq replay pt_regs->softe valueNicholas Piggin1-1/+1
Replayed interrupts get an "artificial" struct pt_regs constructed to pass to interrupt handler functions. This did not get the softe field set correctly, it's as though the interrupt has hit while irqs are disabled. It should be IRQS_ENABLED. This is possibly harmless, asynchronous handlers should not be testing if irqs were disabled, but it might be possible for example some code is shared with synchronous or NMI handlers, and it makes more sense if debug output looks at this. Fixes: 3282a3da25bd ("powerpc/64: Implement soft interrupt replay in C") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200915114650.3980244-2-npiggin@gmail.com
2020-10-06powerpc/64: fix irq replay missing preemptNicholas Piggin1-0/+7
Prior to commit 3282a3da25bd ("powerpc/64: Implement soft interrupt replay in C"), replayed interrupts returned by the regular interrupt exit code, which performs preemption in case an interrupt had set need_resched. This logic was missed by the conversion. Adding preempt_disable/enable around the interrupt replay and final irq enable will reschedule if needed. Fixes: 3282a3da25bd ("powerpc/64: Implement soft interrupt replay in C") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200915114650.3980244-1-npiggin@gmail.com
2020-07-29powerpc/64s: Move HMI IRQ stat from percpu variable to paca.Mahesh Salgaonkar1-3/+6
With the proposed change in percpu bootmem allocator to use page mapping [1], the percpu first chunk memory area can come from vmalloc ranges. This makes the HMI (Hypervisor Maintenance Interrupt) handler crash the kernel whenever percpu variable is accessed in real mode. This patch fixes this issue by moving the HMI IRQ stat inside paca for safe access in realmode. [1] https://lore.kernel.org/linuxppc-dev/20200608070904.387440-1-aneesh.kumar@linux.ibm.com/ Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/159290806973.3642154.5244613424529764050.stgit@jupiter
2020-06-09mm: reorder includes after introduction of linux/pgtable.hMike Rapoport1-1/+1
The replacement of <asm/pgrable.h> with <linux/pgtable.h> made the include of the latter in the middle of asm includes. Fix this up with the aid of the below script and manual adjustments here and there. import sys import re if len(sys.argv) is not 3: print "USAGE: %s <file> <header>" % (sys.argv[0]) sys.exit(1) hdr_to_move="#include <linux/%s>" % sys.argv[2] moved = False in_hdrs = False with open(sys.argv[1], "r") as f: lines = f.readlines() for _line in lines: line = _line.rstrip(' ') if line == hdr_to_move: continue if line.startswith("#include <linux/"): in_hdrs = True elif not moved and in_hdrs: moved = True print hdr_to_move print line Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mm: introduce include/linux/pgtable.hMike Rapoport1-1/+1
The include/linux/pgtable.h is going to be the home of generic page table manipulation functions. Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and make the latter include asm/pgtable.h. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02powerpc: use __vmalloc_node in alloc_vm_stackChristoph Hellwig1-3/+2
alloc_vm_stack can use a slightly higher level vmalloc function. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: Gao Xiang <xiang@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Laura Abbott <labbott@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Kelley <mikelley@microsoft.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Sakari Ailus <sakari.ailus@linux.intel.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Wei Liu <wei.liu@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200414131348.444715-29-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02powerpc/64s: Fix doorbell wakeup msgclr optimisationNicholas Piggin1-0/+13
Commit 3282a3da25bd ("powerpc/64: Implement soft interrupt replay in C") broke the doorbell wakeup optimisation introduced by commit a9af97aa0a12 ("powerpc/64s: msgclr when handling doorbell exceptions from system reset"). This patch restores the msgclr, in C code. It's now done in the system reset wakeup path rather than doorbell interrupt replay where it used to be, because it is always the right thing to do in the wakeup case, but it may be rarely of use in other interrupt replay situations in which case it's wasted work - we would have to run measurements to see if that was a worthwhile optimisation, and I suspect it would not be. The results are similar to those in the original commit, test on POWER8 of context_switch selftests benchmark with polling idle disabled (e.g., always nap, giving cross-CPU IPIs) gives the following results: broken patched Different threads, same core: 317k/s 375k/s +18.7% Different cores: 280k/s 282k/s +1.0% Fixes: 3282a3da25bd ("powerpc/64: Implement soft interrupt replay in C") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200402121212.1118218-1-npiggin@gmail.com
2020-04-01powerpc/64s: Implement interrupt exit logic in CNicholas Piggin1-32/+4
Implement the bulk of interrupt return logic in C. The asm return code must handle a few cases: restoring full GPRs, and emulating stack store. The stack store emulation is significantly simplfied, rather than creating a new return frame and switching to that before performing the store, it uses the PACA to keep a scratch register around to perform the store. The asm return code is moved into 64e for now. The new logic has made allowance for 64e, but I don't have a full environment that works well to test it, and even booting in emulated qemu is not great for stress testing. 64e shouldn't be too far off working with this, given a bit more testing and auditing of the logic. This is slightly faster on a POWER9 (page fault speed increases about 1.1%), probably due to reduced mtmsrd. mpe: Includes fixes from Nick for _TIF_EMULATE_STACK_STORE handling (including the fast_interrupt_return path), to remove trace_hardirqs_on(), and fixes the interrupt-return part of the MSR_VSX restore bug caught by tm-unavailable selftest. mpe: Incorporate fix from Nick: The return-to-kernel path has to replay any soft-pending interrupts if it is returning to a context that had interrupts soft-enabled. It has to do this carefully and avoid plain enabling interrupts if this is an irq context, which can cause multiple nesting of interrupts on the stack, and other unexpected issues. The code which avoided this case got the soft-mask state wrong, and marked interrupts as enabled before going around again to retry. This seems to be mostly harmless except when PREEMPT=y, this calls preempt_schedule_irq with irqs apparently enabled and runs into a BUG in kernel/sched/core.c Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-29-npiggin@gmail.com
2020-04-01powerpc/64: Implement soft interrupt replay in CNicholas Piggin1-35/+130
When local_irq_enable() finds a pending soft-masked interrupt, it "replays" it by setting up registers like the initial interrupt entry, then calls into the low level handler to set up an interrupt stack frame and process the interrupt. This is not necessary, and uses more stack than needed. The high level interrupt handler can be called directly from C, with just pt_regs set up on stack. This should be faster and use less stack. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-28-npiggin@gmail.com
2020-03-04powerpc/irq: Use current_stack_pointer in do_IRQ()Christophe Leroy1-1/+1
Until commit 7306e83ccf5c ("powerpc: Don't use CURRENT_THREAD_INFO to find the stack"), the current stack base address was obtained by calling current_thread_info(). That inline function was simply masking out the value of r1. In that commit, it was changed to using current_stack_pointer() (since renamed current_stack_frame()), which is a heavier function as it is an outline assembly function which cannot be inlined and which reads the content of the stack at 0(r1). Convert to using current_stack_pointer for geting r1 and masking out its value to obtain the base address of the stack pointer as before. Fixes: 7306e83ccf5c ("powerpc: Don't use CURRENT_THREAD_INFO to find the stack") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200220115141.2707-5-mpe@ellerman.id.au
2020-03-04powerpc/irq: use IS_ENABLED() in check_stack_overflow()Christophe Leroy1-2/+3
Instead of #ifdef, use IS_ENABLED(CONFIG_DEBUG_STACKOVERFLOW). This enable GCC to check for code validity even when the option is not selected. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200220115141.2707-4-mpe@ellerman.id.au
2020-03-04powerpc/irq: Use current_stack_pointer in check_stack_overflow()Christophe Leroy1-1/+1
The purpose of check_stack_overflow() is to verify that the stack has not overflowed. To really know whether the stack pointer is still within boundaries, the check must be done directly on the value of r1. So use current_stack_pointer, which returns the current value of r1, rather than current_stack_frame() which causes a frame to be created and then returns that value. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200220115141.2707-3-mpe@ellerman.id.au
2020-03-04powerpc: Rename current_stack_pointer() to current_stack_frame()Michael Ellerman1-2/+2
current_stack_pointer(), which was called __get_SP(), used to just return the value in r1. But that caused problems in some cases, so it was turned into a function in commit bfe9a2cfe91a ("powerpc: Reimplement __get_SP() as a function not a define"). Because it's a function in a separate compilation unit to all its callers, it has the effect of causing a stack frame to be created, and then returns the address of that frame. This is good in some cases like those described in the above commit, but in other cases it's overkill, we just need to know what stack page we're on. On some other arches current_stack_pointer is just a register global giving the stack pointer, and we'd like to do that too. So rename our current_stack_pointer() to current_stack_frame() to make that possible. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Link: https://lore.kernel.org/r/20200220115141.2707-1-mpe@ellerman.id.au
2020-01-27powerpc/32: Use vmapped stacks for interruptsChristophe Leroy1-0/+22
In order to also catch overflows on IRQ stacks, use vmapped stacks. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/d33ad1b36ddff4dcc19f96c592c12a61cf85d406.1576916812.git.christophe.leroy@c-s.fr
2019-12-13powerpc/irq: fix stack overflow verificationChristophe Leroy1-2/+2
Before commit 0366a1c70b89 ("powerpc/irq: Run softirqs off the top of the irq stack"), check_stack_overflow() was called by do_IRQ(), before switching to the irq stack. In that commit, do_IRQ() was renamed __do_irq(), and is now executing on the irq stack, so check_stack_overflow() has just become almost useless. Move check_stack_overflow() call in do_IRQ() to do the check while still on the current stack. Fixes: 0366a1c70b89 ("powerpc/irq: Run softirqs off the top of the irq stack") Cc: stable@vger.kernel.org Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/e033aa8116ab12b7ca9a9c75189ad0741e3b9b5f.1575872340.git.christophe.leroy@c-s.fr
2019-07-14Merge tag 'powerpc-5.3-1' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver, as well as some other functions only used by drivers that haven't (yet?) made it upstream. - A fix for a bug in our handling of hardware watchpoints (eg. perf record -e mem: ...) which could lead to register corruption and kernel crashes. - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for vmalloc when using the Radix MMU. - A large but incremental rewrite of our exception handling code to use gas macros rather than multiple levels of nested CPP macros. And the usual small fixes, cleanups and improvements. Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Cédric Le Goater, Christian Lamparter, Christophe Leroy, Christophe Lombard, Christoph Hellwig, Daniel Axtens, Denis Efremov, Enrico Weigelt, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg Kurz, Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi Bangoria, Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher Boessenkool, Shaokun Zhang, Shawn Anastasio, Stewart Smith, Suraj Jitindar Singh, Thiago Jung Bauermann, YueHaibing" * tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (163 commits) powerpc/powernv/idle: Fix restore of SPRN_LDBAR for POWER9 stop state. powerpc/eeh: Handle hugepages in ioremap space ocxl: Update for AFU descriptor template version 1.1 powerpc/boot: pass CONFIG options in a simpler and more robust way powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h powerpc/irq: Don't WARN continuously in arch_local_irq_restore() powerpc/module64: Use symbolic instructions names. powerpc/module32: Use symbolic instructions names. powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h powerpc/module64: Fix comment in R_PPC64_ENTRY handling powerpc/boot: Add lzo support for uImage powerpc/boot: Add lzma support for uImage powerpc/boot: don't force gzipped uImage powerpc/8xx: Add microcode patch to move SMC parameter RAM. powerpc/8xx: Use IO accessors in microcode programming. powerpc/8xx: replace #ifdefs by IS_ENABLED() in microcode.c powerpc/8xx: refactor programming of microcode CPM params. powerpc/8xx: refactor printing of microcode patch name. powerpc/8xx: Refactor microcode write powerpc/8xx: refactor writing of CPM microcode arrays ...
2019-07-10powerpc/irq: Don't WARN continuously in arch_local_irq_restore()Michael Ellerman1-3/+3
When CONFIG_PPC_IRQ_SOFT_MASK_DEBUG is enabled (uncommon), we have a series of WARN_ON's in arch_local_irq_restore(). These are "should never happen" conditions, but if they do happen they can flood the console and render the system unusable. So switch them to WARN_ON_ONCE(). Fixes: e2b36d591720 ("powerpc/64: Don't trace code that runs with the soft irq mask unreconciled") Fixes: 9b81c0211c24 ("powerpc/64s: make PACA_IRQ_HARD_DIS track MSR[EE] closely") Fixes: 7c0482e3d055 ("powerpc/irq: Fix another case of lazy IRQ state getting out of sync") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190708061046.7075-1-mpe@ellerman.id.au
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner1-5/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-02powerpc/64: Don't trace code that runs with the soft irq mask unreconciledNicholas Piggin1-10/+3
"Reconciling" in terms of interrupt handling, is to bring the soft irq mask state in to synch with the hardware, after an interrupt causes MSR[EE] to be cleared (while the soft mask may be enabled, and hard irqs not marked disabled). General kernel code should not be called while unreconciled, because local_irq_disable, etc. manipulations can cause surprising irq traces, and it's fragile because the soft irq code does not really expect to be called in this situation. When exiting from an interrupt, MSR[EE] is cleared to prevent races, but soft irq state is enabled for the returned-to context, so this is now an unreconciled state. restore_math is called in this state, and that can be ftraced, and the ftrace subsystem disables local irqs. Mark restore_math and its callees as notrace. Restore a sanity check in the soft irq code that had to be disabled for this case, by commit 4da1f79227ad4 ("powerpc/64: Disable irq restore warning for now"). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-02powerpc/irq: drop __irq_offset_valueChristophe Leroy1-3/+0
This patch drops__irq_offset_value which has not been used since commit 9c4cb8251513 ("powerpc: Remove use of CONFIG_PPC_MERGE") This removes a sparse warning. Fixes: 9c4cb8251513 ("powerpc: Remove use of CONFIG_PPC_MERGE") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23powerpc: clean stack pointers namingChristophe Leroy1-10/+7
Some stack pointers used to also be thread_info pointers and were called tp. Now that they are only stack pointers, rename them sp. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23powerpc: regain entire stack spaceChristophe Leroy1-10/+9
thread_info is not anymore in the stack, so the entire stack can now be used. There is also no risk anymore of corrupting task_cpu(p) with a stack overflow so the patch removes the test. When doing this, an explicit test for NULL stack pointer is needed in validate_sp() as it is not anymore implicitely covered by the sizeof(thread_info) gap. In the meantime, with the previous patch all pointers to the stacks are not anymore pointers to thread_info so this patch changes them to void* Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23powerpc: Activate CONFIG_THREAD_INFO_IN_TASKChristophe Leroy1-78/+1
This patch activates CONFIG_THREAD_INFO_IN_TASK which moves the thread_info into task_struct. Moving thread_info into task_struct has the following advantages: - It protects thread_info from corruption in the case of stack overflows. - Its address is harder to determine if stack addresses are leaked, making a number of attacks more difficult. This has the following consequences: - thread_info is now located at the beginning of task_struct. - The 'cpu' field is now in task_struct, and only exists when CONFIG_SMP is active. - thread_info doesn't have anymore the 'task' field. This patch: - Removes all recopy of thread_info struct when the stack changes. - Changes the CURRENT_THREAD_INFO() macro to point to current. - Selects CONFIG_THREAD_INFO_IN_TASK. - Modifies raw_smp_processor_id() to get ->cpu from current without including linux/sched.h to avoid circular inclusion and without including asm/asm-offsets.h to avoid symbol names duplication between ASM constants and C constants. - Modifies klp_init_thread_info() to take a task_struct pointer argument. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Add task_stack.h to livepatch.h to fix build fails] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23powerpc: Don't use CURRENT_THREAD_INFO to find the stackChristophe Leroy1-1/+1
A few places use CURRENT_THREAD_INFO, or the C version, to find the stack. This will no longer work with THREAD_INFO_IN_TASK so change them to find the stack in other ways. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Split out of larger patch] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23powerpc/irq: use memblock functions returning virtual addressChristophe Leroy1-5/+0
Since only the virtual address of allocated blocks is used, lets use functions returning directly virtual address. Those functions have the advantage of also zeroing the block. Suggested-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-14powerpc/irq: drop arch_early_irq_init()Christophe Leroy1-5/+0
arch_early_irq_init() does nothing different than the weak arch_early_irq_init() in kernel/softirq.c Fixes: 089fb442f301 ("powerpc: Use ARCH_IRQ_INIT_FLAGS") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-07powerpc/64: Disable irq restore warning for nowMichael Ellerman1-3/+10
We recently added a warning in arch_local_irq_restore() to check that the soft masking state matches reality. Unfortunately it trips in a few places, which are not entirely trivial to fix. The key problem is if we're doing function_graph tracing of restore_math(), the warning pops and then seems to recurse. It's not entirely clear because the system continuously oopses on all CPUs, with the output interleaved and unreadable. It's also been observed on a G5 coming out of idle. Until we can fix those cases disable the warning for now. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24powerpc/64s: make PACA_IRQ_HARD_DIS track MSR[EE] closelyNicholas Piggin1-10/+24
When the masked interrupt handler clears MSR[EE] for an interrupt in the PACA_IRQ_MUST_HARD_MASK set, it does not set PACA_IRQ_HARD_DIS. This makes them get out of synch. With that taken into account, it's only low level irq manipulation (and interrupt entry before reconcile) where they can be out of synch. This makes the code less surprising. It also allows the IRQ replay code to rely on the IRQ_HARD_DIS value and not have to mtmsrd again in this case (e.g., for an external interrupt that has been masked). The bigger benefit might just be that there is not such an element of surprise in these two bits of state. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/time: account broadcast timer event interrupts separatelyNicholas Piggin1-0/+6
These are not local timer interrupts but IPIs. It's good to be able to see how timer offloading is behaving, so split these out into their own category. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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