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2022-10-25x86/mm: Do not verify W^X at boot upSteven Rostedt (Google)1-0/+4
Adding on the kernel command line "ftrace=function" triggered: CPA detected W^X violation: 8000000000000063 -> 0000000000000063 range: 0xffffffffc0013000 - 0xffffffffc0013fff PFN 10031b WARNING: CPU: 0 PID: 0 at arch/x86/mm/pat/set_memory.c:609 verify_rwx+0x61/0x6d Call Trace: __change_page_attr_set_clr+0x146/0x8a6 change_page_attr_set_clr+0x135/0x268 change_page_attr_clear.constprop.0+0x16/0x1c set_memory_x+0x2c/0x32 arch_ftrace_update_trampoline+0x218/0x2db ftrace_update_trampoline+0x16/0xa1 __register_ftrace_function+0x93/0xb2 ftrace_startup+0x21/0xf0 register_ftrace_function_nolock+0x26/0x40 register_ftrace_function+0x4e/0x143 function_trace_init+0x7d/0xc3 tracer_init+0x23/0x2c tracing_set_tracer+0x1d5/0x206 register_tracer+0x1c0/0x1e4 init_function_trace+0x90/0x96 early_trace_init+0x25c/0x352 start_kernel+0x424/0x6e4 x86_64_start_reservations+0x24/0x2a x86_64_start_kernel+0x8c/0x95 secondary_startup_64_no_verify+0xe0/0xeb This is because at boot up, kernel text is writable, and there's no reason to do tricks to updated it. But the verifier does not distinguish updates at boot up and at run time, and causes a warning at time of boot. Add a check for system_state == SYSTEM_BOOTING and allow it if that is the case. [ These SYSTEM_BOOTING special cases are all pretty horrid, but the x86 text_poke() code does some odd things at bootup, forcing this for now - Linus ] Link: https://lore.kernel.org/r/20221024112730.180916b3@gandalf.local.home Fixes: 652c5bf380ad0 ("x86/mm: Refuse W^X violations") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-10-12treewide: use prandom_u32_max() when possible, part 1Jason A. Donenfeld1-2/+2
Rather than incurring a division or requesting too many random bytes for the given range, use the prandom_u32_max() function, which only takes the minimum required bytes from the RNG and avoids divisions. This was done mechanically with this coccinelle script: @basic@ expression E; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u64; @@ ( - ((T)get_random_u32() % (E)) + prandom_u32_max(E) | - ((T)get_random_u32() & ((E) - 1)) + prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2) | - ((u64)(E) * get_random_u32() >> 32) + prandom_u32_max(E) | - ((T)get_random_u32() & ~PAGE_MASK) + prandom_u32_max(PAGE_SIZE) ) @multi_line@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; identifier RAND; expression E; @@ - RAND = get_random_u32(); ... when != RAND - RAND %= (E); + RAND = prandom_u32_max(E); // Find a potential literal @literal_mask@ expression LITERAL; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; position p; @@ ((T)get_random_u32()@p & (LITERAL)) // Add one to the literal. @script:python add_one@ literal << literal_mask.LITERAL; RESULT; @@ value = None if literal.startswith('0x'): value = int(literal, 16) elif literal[0] in '123456789': value = int(literal, 10) if value is None: print("I don't know how to handle %s" % (literal)) cocci.include_match(False) elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1: print("Skipping 0x%x for cleanup elsewhere" % (value)) cocci.include_match(False) elif value & (value + 1) != 0: print("Skipping 0x%x because it's not a power of two minus one" % (value)) cocci.include_match(False) elif literal.startswith('0x'): coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1)) else: coccinelle.RESULT = cocci.make_expr("%d" % (value + 1)) // Replace the literal mask with the calculated result. @plus_one@ expression literal_mask.LITERAL; position literal_mask.p; expression add_one.RESULT; identifier FUNC; @@ - (FUNC()@p & (LITERAL)) + prandom_u32_max(RESULT) @collapse_ret@ type T; identifier VAR; expression E; @@ { - T VAR; - VAR = (E); - return VAR; + return E; } @drop_var@ type T; identifier VAR; @@ { - T VAR; ... when != VAR } Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: KP Singh <kpsingh@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-10-11Merge tag 'mm-stable-2022-10-08' of ↵Linus Torvalds7-4/+56
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in linux-next for a couple of months without, to my knowledge, any negative reports (or any positive ones, come to that). - Also the Maple Tree from Liam Howlett. An overlapping range-based tree for vmas. It it apparently slightly more efficient in its own right, but is mainly targeted at enabling work to reduce mmap_lock contention. Liam has identified a number of other tree users in the kernel which could be beneficially onverted to mapletrees. Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat at [1]. This has yet to be addressed due to Liam's unfortunately timed vacation. He is now back and we'll get this fixed up. - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses clang-generated instrumentation to detect used-unintialized bugs down to the single bit level. KMSAN keeps finding bugs. New ones, as well as the legacy ones. - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of memory into THPs. - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support file/shmem-backed pages. - userfaultfd updates from Axel Rasmussen - zsmalloc cleanups from Alexey Romanov - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure - Huang Ying adds enhancements to NUMA balancing memory tiering mode's page promotion, with a new way of detecting hot pages. - memcg updates from Shakeel Butt: charging optimizations and reduced memory consumption. - memcg cleanups from Kairui Song. - memcg fixes and cleanups from Johannes Weiner. - Vishal Moola provides more folio conversions - Zhang Yi removed ll_rw_block() :( - migration enhancements from Peter Xu - migration error-path bugfixes from Huang Ying - Aneesh Kumar added ability for a device driver to alter the memory tiering promotion paths. For optimizations by PMEM drivers, DRM drivers, etc. - vma merging improvements from Jakub Matěn. - NUMA hinting cleanups from David Hildenbrand. - xu xin added aditional userspace visibility into KSM merging activity. - THP & KSM code consolidation from Qi Zheng. - more folio work from Matthew Wilcox. - KASAN updates from Andrey Konovalov. - DAMON cleanups from Kaixu Xia. - DAMON work from SeongJae Park: fixes, cleanups. - hugetlb sysfs cleanups from Muchun Song. - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core. Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1] * tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits) hugetlb: allocate vma lock for all sharable vmas hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer hugetlb: fix vma lock handling during split vma and range unmapping mglru: mm/vmscan.c: fix imprecise comments mm/mglru: don't sync disk for each aging cycle mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol mm: memcontrol: use do_memsw_account() in a few more places mm: memcontrol: deprecate swapaccounting=0 mode mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled mm/secretmem: remove reduntant return value mm/hugetlb: add available_huge_pages() func mm: remove unused inline functions from include/linux/mm_inline.h selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd selftests/vm: add thp collapse shmem testing selftests/vm: add thp collapse file and tmpfs testing selftests/vm: modularize thp collapse memory operations selftests/vm: dedup THP helpers mm/khugepaged: add tracepoint to hpage_collapse_scan_file() mm/madvise: add file and shmem support to MADV_COLLAPSE ...
2022-10-11Merge tag 'x86_mm_for_v6.1_rc1' of ↵Linus Torvalds2-11/+57
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Dave Hansen: "There are some small things here, plus one big one. The big one detected and refused to create W+X kernel mappings. This caused a bit of trouble and it is entirely disabled on 32-bit due to known unfixable EFI issues. It also oopsed on some systemd eBPF use, which kept some users from booting. The eBPF issue is fixed, but those troubles were caught relatively recently which made me nervous that there are more lurking. The final commit in here retains the warnings, but doesn't actually refuse to create W+X mappings. Summary: - Detect insecure W+X mappings and warn about them, including a few bug fixes and relaxing the enforcement - Do a long-overdue defconfig update and enabling W+X boot-time detection - Cleanup _PAGE_PSE handling (follow-up on an earlier bug) - Rename a change_page_attr function" * tag 'x86_mm_for_v6.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Ease W^X enforcement back to just a warning x86/mm: Disable W^X detection and enforcement on 32-bit x86/mm: Add prot_sethuge() helper to abstract out _PAGE_PSE handling x86/mm/32: Fix W^X detection when page tables do not support NX x86/defconfig: Enable CONFIG_DEBUG_WX=y x86/defconfig: Refresh the defconfigs x86/mm: Refuse W^X violations x86/mm: Rename set_memory_present() to set_memory_p()
2022-10-04x86/mm: Ease W^X enforcement back to just a warningDave Hansen1-5/+9
Currently, the "change_page_attr" (CPA) code refuses to create W+X mappings on 64-bit kernels. There have been reports both from 32-bit[1] and from BPF[2] users where this change kept the system from booting. These reports are showing up even after about a month of soak time in -next. To avoid breaking anything, never enforce W^X. Always warn and return the requested permissions even if a problem is detected. 1. https://lore.kernel.org/all/CAMj1kXHcF_iK_g0OZSkSv56Wmr=eQGQwNstcNjLEfS=mm7a06w@mail.gmail.com/ 2. https://lore.kernel.org/bpf/c84cc27c1a5031a003039748c3c099732a718aec.camel@kernel.org/T/#u Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: x86@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org>
2022-10-04Merge tag 'x86_cpu_for_v6.1_rc1' of ↵Linus Torvalds1-0/+10
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu updates from Borislav Petkov: - Print the CPU number at segfault time. The number printed is not always accurate (preemption is enabled at that time) but the print string contains "likely" and after a lot of back'n'forth on this, this was the consensus that was reached. See thread at [1]. - After a *lot* of testing and polishing, finally the clear_user() improvements to inline REP; STOSB by default Link: https://lore.kernel.org/r/5d62c1d0-7425-d5bb-ecb5-1dc3b4d7d245@intel.com [1] * tag 'x86_cpu_for_v6.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Print likely CPU at segfault time x86/clear_user: Make it faster
2022-10-04x86: kmsan: handle CPU entry areaAlexander Potapenko2-0/+23
Among other data, CPU entry area holds exception stacks, so addresses from this area can be passed to kmsan_get_metadata(). This previously led to kmsan_get_metadata() returning NULL, which in turn resulted in a warning that triggered further attempts to call kmsan_get_metadata() in the exception context, which quickly exhausted the exception stack. This patch allocates shadow and origin for the CPU entry area on x86 and introduces arch_kmsan_get_meta_or_null(), which performs arch-specific metadata mapping. Link: https://lkml.kernel.org/r/20220928123219.1101883-1-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Fixes: 21d723a7c1409 ("kmsan: add KMSAN runtime core") Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Marco Elver <elver@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-04x86: kmsan: sync metadata pages on page faultAlexander Potapenko1-1/+22
KMSAN assumes shadow and origin pages for every allocated page are accessible. For pages between [VMALLOC_START, VMALLOC_END] those metadata pages start at KMSAN_VMALLOC_SHADOW_START and KMSAN_VMALLOC_ORIGIN_START, therefore we must sync a bigger memory region. Link: https://lkml.kernel.org/r/20220915150417.722975-37-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Marco Elver <elver@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-04x86: kmsan: disable instrumentation of unsupported codeAlexander Potapenko1-0/+2
Instrumenting some files with KMSAN will result in kernel being unable to link, boot or crashing at runtime for various reasons (e.g. infinite recursion caused by instrumentation hooks calling instrumented code again). Completely omit KMSAN instrumentation in the following places: - arch/x86/boot and arch/x86/realmode/rm, as KMSAN doesn't work for i386; - arch/x86/entry/vdso, which isn't linked with KMSAN runtime; - three files in arch/x86/kernel - boot problems; - arch/x86/mm/cpu_entry_area.c - recursion. Link: https://lkml.kernel.org/r/20220915150417.722975-33-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Marco Elver <elver@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-04mm: kmsan: maintain KMSAN metadata for page operationsAlexander Potapenko1-0/+3
Insert KMSAN hooks that make the necessary bookkeeping changes: - poison page shadow and origins in alloc_pages()/free_page(); - clear page shadow and origins in clear_page(), copy_user_highpage(); - copy page metadata in copy_highpage(), wp_page_copy(); - handle vmap()/vunmap()/iounmap(); Link: https://lkml.kernel.org/r/20220915150417.722975-15-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Marco Elver <elver@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-04x86: kmsan: pgtable: reduce vmalloc spaceAlexander Potapenko1-1/+1
KMSAN is going to use 3/4 of existing vmalloc space to hold the metadata, therefore we lower VMALLOC_END to make sure vmalloc() doesn't allocate past the first 1/4. Link: https://lkml.kernel.org/r/20220915150417.722975-10-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Marco Elver <elver@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03x86/mm: Disable W^X detection and enforcement on 32-bitDave Hansen1-0/+8
The 32-bit code is in a weird spot. Some 32-bit builds (non-PAE) do not even have NX support. Even PAE builds that support NX have to contend with things like EFI data and code mixed in the same pages where W+X is unavoidable. The folks still running X86_32=y kernels are unlikely to care much about NX. That combined with the fundamental inability fix _all_ of the W+X things means this code had little value on X86_32=y. Disable the checks. Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Darren Hart <dvhart@infradead.org> Cc: Andy Shevchenko <andy@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: x86@kernel.org Cc: linux-efi@vger.kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/all/CAMj1kXHcF_iK_g0OZSkSv56Wmr=eQGQwNstcNjLEfS=mm7a06w@mail.gmail.com/
2022-09-29x86/mm: Add prot_sethuge() helper to abstract out _PAGE_PSE handlingLinus Torvalds1-9/+10
We still have some historic cases of direct fiddling of page attributes with (dangerous & fragile) type casting and address shifting. Add the prot_sethuge() helper instead that gets the types right and doesn't have to transform addresses. ( Also add a debug check to make sure this doesn't get applied to _PAGE_BIT_PAT/_PAGE_BIT_PAT_LARGE pages. ) Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Dave Hansen <dave.hansen@intel.com>
2022-09-27mm: x86: add CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNGYu Zhao1-1/+4
Some architectures support the accessed bit in non-leaf PMD entries, e.g., x86 sets the accessed bit in a non-leaf PMD entry when using it as part of linear address translation [1]. Page table walkers that clear the accessed bit may use this capability to reduce their search space. Note that: 1. Although an inline function is preferable, this capability is added as a configuration option for consistency with the existing macros. 2. Due to the little interest in other varieties, this capability was only tested on Intel and AMD CPUs. Thanks to the following developers for their efforts [2][3]. Randy Dunlap <rdunlap@infradead.org> Stephen Rothwell <sfr@canb.auug.org.au> [1]: Intel 64 and IA-32 Architectures Software Developer's Manual Volume 3 (June 2021), section 4.8 [2] https://lore.kernel.org/r/bfdcc7c8-922f-61a9-aa15-7e7250f04af7@infradead.org/ [3] https://lore.kernel.org/r/20220413151513.5a0d7a7e@canb.auug.org.au/ Link: https://lkml.kernel.org/r/20220918080010.2920238-3-yuzhao@google.com Signed-off-by: Yu Zhao <yuzhao@google.com> Reviewed-by: Barry Song <baohua@kernel.org> Acked-by: Brian Geffon <bgeffon@google.com> Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org> Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name> Acked-by: Steven Barrett <steven@liquorix.net> Acked-by: Suleiman Souhlal <suleiman@google.com> Tested-by: Daniel Byrne <djbyrne@mtu.edu> Tested-by: Donald Carr <d@chaos-reins.com> Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com> Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru> Tested-by: Shuang Zhai <szhai2@cs.rochester.edu> Tested-by: Sofia Trinh <sofia.trinh@edi.works> Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michael Larabel <Michael@MichaelLarabel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-27mm/swap: cache maximum swapfile size when init swapPeter Xu1-1/+1
We used to have swapfile_maximum_size() fetching a maximum value of swapfile size per-arch. As the caller of max_swapfile_size() grows, this patch introduce a variable "swapfile_maximum_size" and cache the value of old max_swapfile_size(), so that we don't need to calculate the value every time. Caching the value in swapfile_init() is safe because when reaching the phase we should have initialized all the relevant information. Here the major arch to take care of is x86, which defines the max swapfile size based on L1TF mitigation. Here both X86_BUG_L1TF or l1tf_mitigation should have been setup properly when reaching swapfile_init(). As a reference, the code path looks like this for x86: - start_kernel - setup_arch - early_cpu_init - early_identify_cpu --> setup X86_BUG_L1TF - parse_early_param - l1tf_cmdline --> set l1tf_mitigation - check_bugs - l1tf_select_mitigation --> set l1tf_mitigation - arch_call_rest_init - rest_init - kernel_init - kernel_init_freeable - do_basic_setup - do_initcalls --> calls swapfile_init() (initcall level 4) The swapfile size only depends on swp pte format on non-x86 archs, so caching it is safe too. Since at it, rename max_swapfile_size() to arch_max_swapfile_size() because arch can define its own function, so it's more straightforward to have "arch_" as its prefix. At the meantime, export swapfile_maximum_size to replace the old usages of max_swapfile_size(). [peterx@redhat.com: declare arch_max_swapfile_size) in swapfile.h] Link: https://lkml.kernel.org/r/YxTh1GuC6ro5fKL5@xz-m1.local Link: https://lkml.kernel.org/r/20220811161331.37055-7-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: "Kirill A . Shutemov" <kirill@shutemov.name> Cc: Minchan Kim <minchan@kernel.org> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-21x86/mm/32: Fix W^X detection when page tables do not support NXDave Hansen1-1/+2
The x86 MM code now actively refuses to create writable+executable mappings, and warns when there is an attempt to create one. The 0day test robot ran across a warning triggered by module unloading on 32-bit kernels. This was only seen on CPUs with NX support, but where a 32-bit kernel was built without PAE support. On those systems, there is no room for the NX bit in the page tables and _PAGE_NX is #defined to 0, breaking some of the W^X detection logic in verify_rwx(). The X86_FEATURE_NX check in there does not do any good here because the CPU itself supports NX. Fix it by checking for _PAGE_NX support directly instead of checking CPU support for NX. Note that since _PAGE_NX is actually defined to be 0 at compile-time this fix should also end up letting the compiler optimize away most of verify_rwx() on non-PAE kernels. Fixes: 652c5bf380ad ("x86/mm: Refuse W^X violations") Reported-by: kernel test robot <yujie.liu@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/fcf89147-440b-e478-40c9-228c9fe56691@intel.com/
2022-09-12x86/mm: disable instrumentations of mm/pgprot.cNaohiro Aota1-0/+3
Commit 4867fbbdd6b3 ("x86/mm: move protection_map[] inside the platform") moved accesses to protection_map[] from mem_encrypt_amd.c to pgprot.c. As a result, the accesses are now targets of KASAN (and other instrumentations), leading to the crash during the boot process. Disable the instrumentations for pgprot.c like commit 67bb8e999e0a ("x86/mm: Disable various instrumentations of mm/mem_encrypt.c and mm/tlb.c"). Before this patch, my AMD machine cannot boot since v6.0-rc1 with KASAN enabled, without anything printed. After the change, it successfully boots up. Fixes: 4867fbbdd6b3 ("x86/mm: move protection_map[] inside the platform") Link: https://lkml.kernel.org/r/20220824084726.2174758-1-naohiro.aota@wdc.com Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-02Merge branch 'linus' into x86/mm, to refresh the branchIngo Molnar8-51/+111
This branch is ~14k commits behind upstream, and has an old merge base from early into the merge window, refresh it to v6.0-rc3+fixes before queueing up new commits. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2022-09-01x86/mm: Refuse W^X violationsPeter Zijlstra1-0/+32
x86 has STRICT_*_RWX, but not even a warning when someone violates it. Add this warning and fully refuse the transition. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lkml.kernel.org/r/YwySW3ROc21hN7g9@hirez.programming.kicks-ass.net
2022-08-28Merge tag 'x86-urgent-2022-08-28' of ↵Linus Torvalds1-1/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 fixes from Ingo Molnar: - Fix PAT on Xen, which caused i915 driver failures - Fix compat INT 80 entry crash on Xen PV guests - Fix 'MMIO Stale Data' mitigation status reporting on older Intel CPUs - Fix RSB stuffing regressions - Fix ORC unwinding on ftrace trampolines - Add Intel Raptor Lake CPU model number - Fix (work around) a SEV-SNP bootloader bug providing bogus values in boot_params->cc_blob_address, by ignoring the value on !SEV-SNP bootups. - Fix SEV-SNP early boot failure - Fix the objtool list of noreturn functions and annotate snp_abort(), which bug confused objtool on gcc-12. - Fix the documentation for retbleed * tag 'x86-urgent-2022-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Documentation/ABI: Mention retbleed vulnerability info file for sysfs x86/sev: Mark snp_abort() noreturn x86/sev: Don't use cc_platform_has() for early SEV-SNP calls x86/boot: Don't propagate uninitialized boot_params->cc_blob_address x86/cpu: Add new Raptor Lake CPU model number x86/unwind/orc: Unwind ftrace trampolines with correct ORC entry x86/nospec: Fix i386 RSB stuffing x86/nospec: Unwreck the RSB stuffing x86/bugs: Add "unknown" reporting for MMIO Stale Data x86/entry: Fix entry_INT80_compat for Xen PV guests x86/PAT: Have pat_enabled() properly reflect state when running on Xen
2022-08-24x86/mm: Print likely CPU at segfault timeRik van Riel1-0/+10
In a large enough fleet of computers, it is common to have a few bad CPUs. Those can often be identified by seeing that some commonly run kernel code, which runs fine everywhere else, keeps crashing on the same CPU core on one particular bad system. However, the failure modes in CPUs that have gone bad over the years are often oddly specific, and the only bad behavior seen might be segfaults in programs like bash, python, or various system daemons that run fine everywhere else. Add a printk() to show_signal_msg() to print the CPU, core, and socket at segfault time. This is not perfect, since the task might get rescheduled on another CPU between when the fault hit, and when the message is printed, but in practice this has been good enough to help people identify several bad CPU cores. For example: segfault[1349]: segfault at 0 ip 000000000040113a sp 00007ffc6d32e360 error 4 in \ segfault[401000+1000] likely on CPU 0 (core 0, socket 0) This printk can be controlled through /proc/sys/debug/exception-trace. [ bp: Massage a bit, add "likely" to the printed line to denote that the CPU number is not always reliable. ] Signed-off-by: Rik van Riel <riel@surriel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20220805101644.2e674553@imladris.surriel.com
2022-08-19x86/mm: Use proper mask when setting PUD mappingAaron Lu1-1/+1
Commit c164fbb40c43f("x86/mm: thread pgprot_t through init_memory_mapping()") mistakenly used __pgprot() which doesn't respect __default_kernel_pte_mask when setting PUD mapping. Fix it by only setting the one bit we actually need (PSE) and leaving the other bits (that have been properly masked) alone. Fixes: c164fbb40c43 ("x86/mm: thread pgprot_t through init_memory_mapping()") Signed-off-by: Aaron Lu <aaron.lu@intel.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-08-16x86: simplify load_unaligned_zeropad() implementationLinus Torvalds1-0/+55
The exception for the "unaligned access at the end of the page, next page not mapped" never happens, but the fixup code ends up causing trouble for compilers to optimize well. clang in particular ends up seeing it being in the middle of a loop, and tries desperately to optimize the exception fixup code that is never really reached. The simple solution is to just move all the fixups into the exception handler itself, which moves it all out of the hot case code, and means that the compiler never sees it or needs to worry about it. Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-08-15x86/PAT: Have pat_enabled() properly reflect state when running on XenJan Beulich1-1/+9
After commit ID in the Fixes: tag, pat_enabled() returns false (because of PAT initialization being suppressed in the absence of MTRRs being announced to be available). This has become a problem: the i915 driver now fails to initialize when running PV on Xen (i915_gem_object_pin_map() is where I located the induced failure), and its error handling is flaky enough to (at least sometimes) result in a hung system. Yet even beyond that problem the keying of the use of WC mappings to pat_enabled() (see arch_can_pci_mmap_wc()) means that in particular graphics frame buffer accesses would have been quite a bit less optimal than possible. Arrange for the function to return true in such environments, without undermining the rest of PAT MSR management logic considering PAT to be disabled: specifically, no writes to the PAT MSR should occur. For the new boolean to live in .init.data, init_cache_modes() also needs moving to .init.text (where it could/should have lived already before). [ bp: This is the "small fix" variant for stable. It'll get replaced with a proper PAT and MTRR detection split upstream but that is too involved for a stable backport. - additional touchups to commit msg. Use cpu_feature_enabled(). ] Fixes: bdd8b6c98239 ("drm/i915: replace X86_FEATURE_PAT with pat_enabled()") Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: <stable@vger.kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: Lucas De Marchi <lucas.demarchi@intel.com> Link: https://lore.kernel.org/r/9385fa60-fa5d-f559-a137-6608408f88b0@suse.com
2022-08-09mm/hugetlb: make pud_huge() and follow_huge_pud() aware of non-present pud entryNaoya Horiguchi1-1/+7
follow_pud_mask() does not support non-present pud entry now. As long as I tested on x86_64 server, follow_pud_mask() still simply returns no_page_table() for non-present_pud_entry() due to pud_bad(), so no severe user-visible effect should happen. But generally we should call follow_huge_pud() for non-present pud entry for 1GB hugetlb page. Update pud_huge() and follow_huge_pud() to handle non-present pud entries. The changes are similar to previous works for pud entries commit e66f17ff7177 ("mm/hugetlb: take page table lock in follow_huge_pmd()") and commit cbef8478bee5 ("mm/hugetlb: pmd_huge() returns true for non-present hugepage"). Link: https://lkml.kernel.org/r/20220714042420.1847125-3-naoya.horiguchi@linux.dev Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: David Hildenbrand <david@redhat.com> Cc: kernel test robot <lkp@intel.com> Cc: Liu Shixin <liushixin2@huawei.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-08-07Merge tag 'x86-urgent-2022-08-06' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: - build fix for old(er) binutils - build fix for new GCC - kexec boot environment fix * tag 'x86-urgent-2022-08-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/entry: Build thunk_$(BITS) only if CONFIG_PREEMPTION=y x86/numa: Use cpumask_available instead of hardcoded NULL check x86/bus_lock: Don't assume the init value of DEBUGCTLMSR.BUS_LOCK_DETECT to be zero
2022-08-06x86/mm: Rename set_memory_present() to set_memory_p()Borislav Petkov1-2/+2
Have it adhere to the naming convention for those helpers. No functional changes. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20220805140702.31538-1-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2022-08-06Merge tag 'mm-stable-2022-08-03' of ↵Linus Torvalds4-43/+34
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Most of the MM queue. A few things are still pending. Liam's maple tree rework didn't make it. This has resulted in a few other minor patch series being held over for next time. Multi-gen LRU still isn't merged as we were waiting for mapletree to stabilize. The current plan is to merge MGLRU into -mm soon and to later reintroduce mapletree, with a view to hopefully getting both into 6.1-rc1. Summary: - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe Lin, Yang Shi, Anshuman Khandual and Mike Rapoport - Some kmemleak fixes from Patrick Wang and Waiman Long - DAMON updates from SeongJae Park - memcg debug/visibility work from Roman Gushchin - vmalloc speedup from Uladzislau Rezki - more folio conversion work from Matthew Wilcox - enhancements for coherent device memory mapping from Alex Sierra - addition of shared pages tracking and CoW support for fsdax, from Shiyang Ruan - hugetlb optimizations from Mike Kravetz - Mel Gorman has contributed some pagealloc changes to improve latency and realtime behaviour. - mprotect soft-dirty checking has been improved by Peter Xu - Many other singleton patches all over the place" [ XFS merge from hell as per Darrick Wong in https://lore.kernel.org/all/YshKnxb4VwXycPO8@magnolia/ ] * tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (282 commits) tools/testing/selftests/vm/hmm-tests.c: fix build mm: Kconfig: fix typo mm: memory-failure: convert to pr_fmt() mm: use is_zone_movable_page() helper hugetlbfs: fix inaccurate comment in hugetlbfs_statfs() hugetlbfs: cleanup some comments in inode.c hugetlbfs: remove unneeded header file hugetlbfs: remove unneeded hugetlbfs_ops forward declaration hugetlbfs: use helper macro SZ_1{K,M} mm: cleanup is_highmem() mm/hmm: add a test for cross device private faults selftests: add soft-dirty into run_vmtests.sh selftests: soft-dirty: add test for mprotect mm/mprotect: fix soft-dirty check in can_change_pte_writable() mm: memcontrol: fix potential oom_lock recursion deadlock mm/gup.c: fix formatting in check_and_migrate_movable_page() xfs: fail dax mount if reflink is enabled on a partition mm/memcontrol.c: remove the redundant updating of stats_flush_threshold userfaultfd: don't fail on unrecognized features hugetlb_cgroup: fix wrong hugetlb cgroup numa stat ...
2022-08-05Merge tag 'for-linus-6.0-rc1-tag' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - a series fine tuning virtio support for Xen guests, including removal the now again unused "platform_has()" feature. - a fix for host admin triggered reboot of Xen guests - a simple spelling fix * tag 'for-linus-6.0-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: don't require virtio with grants for non-PV guests kernel: remove platform_has() infrastructure virtio: replace restricted mem access flag with callback xen: Fix spelling mistake xen/manage: Use orderly_reboot() to reboot
2022-08-03x86/numa: Use cpumask_available instead of hardcoded NULL checkSiddh Raman Pant1-2/+2
GCC-12 started triggering a new warning: arch/x86/mm/numa.c: In function ‘cpumask_of_node’: arch/x86/mm/numa.c:916:39: warning: the comparison will always evaluate as ‘false’ for the address of ‘node_to_cpumask_map’ will never be NULL [-Waddress] 916 | if (node_to_cpumask_map[node] == NULL) { | ^~ node_to_cpumask_map is of type cpumask_var_t[]. When CONFIG_CPUMASK_OFFSTACK is set, cpumask_var_t is typedef'd to a pointer for dynamic allocation, else to an array of one element. The "wicked game" can be checked on line 700 of include/linux/cpumask.h. The original code in debug_cpumask_set_cpu() and cpumask_of_node() were probably written by the original authors with CONFIG_CPUMASK_OFFSTACK=y (i.e. dynamic allocation) in mind, checking if the cpumask was available via a direct NULL check. When CONFIG_CPUMASK_OFFSTACK is not set, GCC gives the above warning while compiling the kernel. Fix that by using cpumask_available(), which does the NULL check when CONFIG_CPUMASK_OFFSTACK is set, otherwise returns true. Use it wherever such checks are made. Conditional definitions of cpumask_available() can be found along with the definition of cpumask_var_t. Check the cpumask.h reference mentioned above. Fixes: c032ef60d1aa ("cpumask: convert node_to_cpumask_map[] to cpumask_var_t") Fixes: de2d9445f162 ("x86: Unify node_to_cpumask_map handling between 32 and 64bit") Signed-off-by: Siddh Raman Pant <code@siddh.me> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20220731160913.632092-1-code@siddh.me
2022-08-03Merge tag 'rcu.2022.07.26a' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu Pull RCU updates from Paul McKenney: - Documentation updates - Miscellaneous fixes - Callback-offload updates, perhaps most notably a new RCU_NOCB_CPU_DEFAULT_ALL Kconfig option that causes all CPUs to be offloaded at boot time, regardless of kernel boot parameters. This is useful to battery-powered systems such as ChromeOS and Android. In addition, a new RCU_NOCB_CPU_CB_BOOST kernel boot parameter prevents offloaded callbacks from interfering with real-time workloads and with energy-efficiency mechanisms - Polled grace-period updates, perhaps most notably making these APIs account for both normal and expedited grace periods - Tasks RCU updates, perhaps most notably reducing the CPU overhead of RCU tasks trace grace periods by more than a factor of two on a system with 15,000 tasks. The reduction is expected to increase with the number of tasks, so it seems reasonable to hypothesize that a system with 150,000 tasks might see a 20-fold reduction in CPU overhead - Torture-test updates - Updates that merge RCU's dyntick-idle tracking into context tracking, thus reducing the overhead of transitioning to kernel mode from either idle or nohz_full userspace execution for kernels that track context independently of RCU. This is expected to be helpful primarily for kernels built with CONFIG_NO_HZ_FULL=y * tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (98 commits) rcu: Add irqs-disabled indicator to expedited RCU CPU stall warnings rcu: Diagnose extended sync_rcu_do_polled_gp() loops rcu: Put panic_on_rcu_stall() after expedited RCU CPU stall warnings rcutorture: Test polled expedited grace-period primitives rcu: Add polled expedited grace-period primitives rcutorture: Verify that polled GP API sees synchronous grace periods rcu: Make Tiny RCU grace periods visible to polled APIs rcu: Make polled grace-period API account for expedited grace periods rcu: Switch polled grace-period APIs to ->gp_seq_polled rcu/nocb: Avoid polling when my_rdp->nocb_head_rdp list is empty rcu/nocb: Add option to opt rcuo kthreads out of RT priority rcu: Add nocb_cb_kthread check to rcu_is_callbacks_kthread() rcu/nocb: Add an option to offload all CPUs on boot rcu/nocb: Fix NOCB kthreads spawn failure with rcu_nocb_rdp_deoffload() direct call rcu/nocb: Invert rcu_state.barrier_mutex VS hotplug lock locking order rcu/nocb: Add/del rdp to iterate from rcuog itself rcu/tree: Add comment to describe GP-done condition in fqs loop rcu: Initialize first_gp_fqs at declaration in rcu_gp_fqs() rcu/kvfree: Remove useless monitor_todo flag rcu: Cleanup RCU urgency state for offline CPU ...
2022-08-01Merge tag 'x86_core_for_v6.0_rc1' of ↵Linus Torvalds1-7/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core updates from Borislav Petkov: - Have invalid MSR accesses warnings appear only once after a pr_warn_once() change broke that - Simplify {JMP,CALL}_NOSPEC and let the objtool retpoline patching infra take care of them instead of having unreadable alternative macros there * tag 'x86_core_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/extable: Fix ex_handler_msr() print condition x86,nospec: Simplify {JMP,CALL}_NOSPEC
2022-08-01Merge tag 'x86_mm_for_v6.0_rc1' of ↵Linus Torvalds2-9/+37
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Borislav Petkov: - Rename a PKRU macro to make more sense when reading the code - Update pkeys documentation - Avoid reading contended mm's TLB generation var if not absolutely necessary along with fixing a case where arch_tlbbatch_flush() doesn't adhere to the generation scheme and thus violates the conditions for the above avoidance. * tag 'x86_mm_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm/tlb: Ignore f->new_tlb_gen when zero x86/pkeys: Clarify PKRU_AD_KEY macro Documentation/protection-keys: Clean up documentation for User Space pkeys x86/mm/tlb: Avoid reading mm_tlb_gen when possible
2022-08-01Merge tag 'x86_cleanups_for_v6.0_rc1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanup from Borislav Petkov: - A single CONFIG_ symbol correction in a comment * tag 'x86_cleanups_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Refer to the intended config STRICT_DEVMEM in a comment
2022-08-01virtio: replace restricted mem access flag with callbackJuergen Gross1-2/+2
Instead of having a global flag to require restricted memory access for all virtio devices, introduce a callback which can select that requirement on a per-device basis. For convenience add a common function returning always true, which can be used for use cases like SEV. Per default use a callback always returning false. As the callback needs to be set in early init code already, add a virtio anchor which is builtin in case virtio is enabled. Signed-off-by: Juergen Gross <jgross@suse.com> Tested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Arm64 guest using Xen Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/20220622063838.8854-2-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-07-21x86/extable: Fix ex_handler_msr() print conditionPeter Zijlstra1-7/+9
On Fri, Jun 17, 2022 at 02:08:52PM +0300, Stephane Eranian wrote: > Some changes to the way invalid MSR accesses are reported by the > kernel is causing some problems with messages printed on the > console. > > We have seen several cases of ex_handler_msr() printing invalid MSR > accesses once but the callstack multiple times causing confusion on > the console. > The problem here is that another earlier commit (5.13): > > a358f40600b3 ("once: implement DO_ONCE_LITE for non-fast-path "do once" functionality") > > Modifies all the pr_*_once() calls to always return true claiming > that no caller is ever checking the return value of the functions. > > This is why we are seeing the callstack printed without the > associated printk() msg. Extract the ONCE_IF(cond) part into __ONCE_LTE_IF() and use that to implement DO_ONCE_LITE_IF() and fix the extable code. Fixes: a358f40600b3 ("once: implement DO_ONCE_LITE for non-fast-path "do once" functionality") Reported-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Stephane Eranian <eranian@google.com> Link: https://lkml.kernel.org/r/YqyVFsbviKjVGGZ9@worktop.programming.kicks-ass.net
2022-07-19x86/mm/tlb: Ignore f->new_tlb_gen when zeroNadav Amit1-3/+12
Commit aa44284960d5 ("x86/mm/tlb: Avoid reading mm_tlb_gen when possible") introduced an optimization to skip superfluous TLB flushes based on the generation provided in flush_tlb_info. However, arch_tlbbatch_flush() does not provide any generation in flush_tlb_info and populates the flush_tlb_info generation with 0. This 0 is causes the flush_tlb_info to be interpreted as a superfluous, old flush. As a result, try_to_unmap_one() would not perform any TLB flushes. Fix it by checking whether f->new_tlb_gen is nonzero. Zero value is anyhow is an invalid generation value. To avoid future confusion, introduce TLB_GENERATION_INVALID constant and use it properly. Add warnings to ensure no partial flushes are done with TLB_GENERATION_INVALID or when f->mm is NULL, since this does not make any sense. In addition, add the missing unlikely(). [ dhansen: change VM_BUG_ON() -> VM_WARN_ON(), clarify changelog ] Fixes: aa44284960d5 ("x86/mm/tlb: Avoid reading mm_tlb_gen when possible") Reported-by: Hugh Dickins <hughd@google.com> Signed-off-by: Nadav Amit <namit@vmware.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Tested-by: Hugh Dickins <hughd@google.com> Link: https://lkml.kernel.org/r/20220710232837.3618-1-namit@vmware.com
2022-07-18x86/mm: move protection_map[] inside the platformAnshuman Khandual2-4/+30
This moves protection_map[] inside the platform and makes it a static. This also defines a helper function add_encrypt_protection_map() that can update the protection_map[] array with pgprot_encrypted(). Link: https://lkml.kernel.org/r/20220711070600.2378316-7-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Brian Cain <bcain@quicinc.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Christoph Hellwig <hch@infradead.org> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-13x86/pat: Fix x86_has_pat_wp()Juergen Gross1-2/+12
x86_has_pat_wp() is using a wrong test, as it relies on the normal PAT configuration used by the kernel. In case the PAT MSR has been setup by another entity (e.g. Xen hypervisor) it might return false even if the PAT configuration is allowing WP mappings. This due to the fact that when running as Xen PV guest the PAT MSR is setup by the hypervisor and cannot be changed by the guest. This results in the WP related entry to be at a different position when running as Xen PV guest compared to the bare metal or fully virtualized case. The correct way to test for WP support is: 1. Get the PTE protection bits needed to select WP mode by reading __cachemode2pte_tbl[_PAGE_CACHE_MODE_WP] (depending on the PAT MSR setting this might return protection bits for a stronger mode, e.g. UC-) 2. Translate those bits back into the real cache mode selected by those PTE bits by reading __pte2cachemode_tbl[__pte2cm_idx(prot)] 3. Test for the cache mode to be _PAGE_CACHE_MODE_WP Fixes: f88a68facd9a ("x86/mm: Extend early_memremap() support with additional attrs") Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> # 4.14 Link: https://lore.kernel.org/r/20220503132207.17234-1-jgross@suse.com
2022-07-07x86/mm: Refer to the intended config STRICT_DEVMEM in a commentLukas Bulwahn1-1/+1
Commit a4866aa81251 ("mm: Tighten x86 /dev/mem with zeroing reads") adds a comment to the function devmem_is_allowed() referring to a non-existing config STRICT_IOMEM, whereas the comment very likely intended to refer to the config STRICT_DEVMEM, as the commit adds some behavior for the config STRICT_DEVMEM. Most of the initial analysis was actually done by Dave Hansen in the email thread below (see Link). Refer to the intended and existing config STRICT_DEVMEM. Suggested-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/r/f9074e8d-9314-9d7d-7bf5-5b5538c8be8d@intel.com/ Link: https://lkml.kernel.org/r/20220707115442.21107-1-lukas.bulwahn@gmail.com
2022-07-05context_tracking: Take IRQ eqs entrypoints over RCUFrederic Weisbecker1-1/+1
The RCU dynticks counter is going to be merged into the context tracking subsystem. Prepare with moving the IRQ extended quiescent states entrypoints to context tracking. For now those are dumb redirection to existing RCU calls. [ paulmck: Apply Stephen Rothwell feedback from -next. ] [ paulmck: Apply Nathan Chancellor feedback. ] Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com> Cc: Uladzislau Rezki <uladzislau.rezki@sony.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Nicolas Saenz Julienne <nsaenz@kernel.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com> Cc: Yu Liao <liaoyu15@huawei.com> Cc: Phil Auld <pauld@redhat.com> Cc: Paul Gortmaker<paul.gortmaker@windriver.com> Cc: Alex Belits <abelits@marvell.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
2022-06-27objtool: Update Retpoline validationPeter Zijlstra1-0/+2
Update retpoline validation with the new CONFIG_RETPOLINE requirement of not having bare naked RET instructions. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-27x86/sev: Avoid using __x86_return_thunkKim Phillips1-2/+6
Specifically, it's because __enc_copy() encrypts the kernel after being relocated outside the kernel in sme_encrypt_execute(), and the RET macro's jmp offset isn't amended prior to execution. Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-17mm: avoid unnecessary page fault retires on shared memory typesPeter Xu1-0/+4
I observed that for each of the shared file-backed page faults, we're very likely to retry one more time for the 1st write fault upon no page. It's because we'll need to release the mmap lock for dirty rate limit purpose with balance_dirty_pages_ratelimited() (in fault_dirty_shared_page()). Then after that throttling we return VM_FAULT_RETRY. We did that probably because VM_FAULT_RETRY is the only way we can return to the fault handler at that time telling it we've released the mmap lock. However that's not ideal because it's very likely the fault does not need to be retried at all since the pgtable was well installed before the throttling, so the next continuous fault (including taking mmap read lock, walk the pgtable, etc.) could be in most cases unnecessary. It's not only slowing down page faults for shared file-backed, but also add more mmap lock contention which is in most cases not needed at all. To observe this, one could try to write to some shmem page and look at "pgfault" value in /proc/vmstat, then we should expect 2 counts for each shmem write simply because we retried, and vm event "pgfault" will capture that. To make it more efficient, add a new VM_FAULT_COMPLETED return code just to show that we've completed the whole fault and released the lock. It's also a hint that we should very possibly not need another fault immediately on this page because we've just completed it. This patch provides a ~12% perf boost on my aarch64 test VM with a simple program sequentially dirtying 400MB shmem file being mmap()ed and these are the time it needs: Before: 650.980 ms (+-1.94%) After: 569.396 ms (+-1.38%) I believe it could help more than that. We need some special care on GUP and the s390 pgfault handler (for gmap code before returning from pgfault), the rest changes in the page fault handlers should be relatively straightforward. Another thing to mention is that mm_account_fault() does take this new fault as a generic fault to be accounted, unlike VM_FAULT_RETRY. I explicitly didn't touch hmm_vma_fault() and break_ksm() because they do not handle VM_FAULT_RETRY even with existing code, so I'm literally keeping them as-is. Link: https://lkml.kernel.org/r/20220530183450.42886-1-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Vineet Gupta <vgupta@kernel.org> Acked-by: Guo Ren <guoren@kernel.org> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm part] Acked-by: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Stafford Horne <shorne@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Brian Cain <bcain@quicinc.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Richard Weinberger <richard@nod.at> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Janosch Frank <frankja@linux.ibm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Will Deacon <will@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Simek <monstr@monstr.eu> Cc: Matt Turner <mattst88@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: David Hildenbrand <david@redhat.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Chris Zankel <chris@zankel.net> Cc: Hugh Dickins <hughd@google.com> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Rich Felker <dalias@libc.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Helge Deller <deller@gmx.de> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-06-17mm/x86: remove dead code for hugetlbpage.cPeter Xu1-39/+0
It seems to exist since the old times and never used once. Remove them. Link: https://lkml.kernel.org/r/20220525195220.10241-1-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Acked-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-06-08x86/pkeys: Clarify PKRU_AD_KEY macroIra Weiny1-6/+9
When changing the PKRU_AD_KEY macro to be used for PKS the name came into question.[1] The intent of PKRU_AD_KEY is to set an initial value for the PKRU register but that is just a mask value. Clarify this by changing the name to PKRU_AD_MASK(). NOTE the checkpatch errors are ignored for the init_pkru_value to align the values in the code. [1] https://lore.kernel.org/lkml/eff862e2-bfaa-9e12-42b5-a12467d72a22@intel.com/ Suggested-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lkml.kernel.org/r/20220419170649.1022246-3-ira.weiny@intel.com
2022-06-07x86/mm/tlb: Avoid reading mm_tlb_gen when possibleNadav Amit1-1/+17
On extreme TLB shootdown storms, the mm's tlb_gen cacheline is highly contended and reading it should (arguably) be avoided as much as possible. Currently, flush_tlb_func() reads the mm's tlb_gen unconditionally, even when it is not necessary (e.g., the mm was already switched). This is wasteful. Moreover, one of the existing optimizations is to read mm's tlb_gen to see if there are additional in-flight TLB invalidations and flush the entire TLB in such a case. However, if the request's tlb_gen was already flushed, the benefit of checking the mm's tlb_gen is likely to be offset by the overhead of the check itself. Running will-it-scale with tlb_flush1_threads show a considerable benefit on 56-core Skylake (up to +24%): threads Baseline (v5.17+) +Patch 1 159960 160202 5 310808 308378 (-0.7%) 10 479110 490728 15 526771 562528 20 534495 587316 25 547462 628296 30 579616 666313 35 594134 701814 40 612288 732967 45 617517 749727 50 637476 735497 55 614363 778913 (+24%) Signed-off-by: Nadav Amit <namit@vmware.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/20220606180123.2485171-1-namit@vmware.com
2022-06-06virtio: replace arch_has_restricted_virtio_memory_access()Juergen Gross2-7/+4
Instead of using arch_has_restricted_virtio_memory_access() together with CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS, replace those with platform_has() and a new platform feature PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Tested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Arm64 only Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Borislav Petkov <bp@suse.de>
2022-06-05Merge tag 'x86-mm-2022-06-05' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm cleanup from Thomas Gleixner: "Use PAGE_ALIGNED() instead of open coding it in the x86/mm code" * tag 'x86-mm-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Use PAGE_ALIGNED(x) instead of IS_ALIGNED(x, PAGE_SIZE)
2022-05-28Merge tag 'libnvdimm-for-5.19' of ↵Linus Torvalds1-2/+47
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm and DAX updates from Dan Williams: "New support for clearing memory errors when a file is in DAX mode, alongside with some other fixes and cleanups. Previously it was only possible to clear these errors using a truncate or hole-punch operation to trigger the filesystem to reallocate the block, now, any page aligned write can opportunistically clear errors as well. This change spans x86/mm, nvdimm, and fs/dax, and has received the appropriate sign-offs. Thanks to Jane for her work on this. Summary: - Add support for clearing memory error via pwrite(2) on DAX - Fix 'security overwrite' support in the presence of media errors - Miscellaneous cleanups and fixes for nfit_test (nvdimm unit tests)" * tag 'libnvdimm-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: pmem: implement pmem_recovery_write() pmem: refactor pmem_clear_poison() dax: add .recovery_write dax_operation dax: introduce DAX_RECOVERY_WRITE dax access mode mce: fix set_mce_nospec to always unmap the whole page x86/mce: relocate set{clear}_mce_nospec() functions acpi/nfit: rely on mce->misc to determine poison granularity testing: nvdimm: asm/mce.h is not needed in nfit.c testing: nvdimm: iomap: make __nfit_test_ioremap a macro nvdimm: Allow overwrite in the presence of disabled dimms tools/testing/nvdimm: remove unneeded flush_workqueue
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