- 07 Aug, 2020 40 commits
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Anshuman Khandual authored
This adds a specific description file for all arch page table helpers which is in sync with the semantics being tested via CONFIG_DEBUG_VM_PGTABLE. All future changes either to these descriptions here or the debug test should always remain in sync. [anshuman.khandual@arm.com: fold in Mike's patch for the rst document, fix typos in the rst document] Link: http://lkml.kernel.org/r/1594610587-4172-5-git-send-email-anshuman.khandual@arm.comSuggested-by: Mike Rapoport <rppt@kernel.org> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Zi Yan <ziy@nvidia.com> Link: http://lkml.kernel.org/r/1593996516-7186-5-git-send-email-anshuman.khandual@arm.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Anshuman Khandual authored
This adds debug print information that enlists all tests getting executed on a given platform. With dynamic debug enabled, the following information will be splashed during boot. For compactness purpose, dropped both time stamp and prefix (i.e debug_vm_pgtable) from this sample output. [debug_vm_pgtable ]: Validating architecture page table helpers [pte_basic_tests ]: Validating PTE basic [pmd_basic_tests ]: Validating PMD basic [p4d_basic_tests ]: Validating P4D basic [pgd_basic_tests ]: Validating PGD basic [pte_clear_tests ]: Validating PTE clear [pmd_clear_tests ]: Validating PMD clear [pte_advanced_tests ]: Validating PTE advanced [pmd_advanced_tests ]: Validating PMD advanced [hugetlb_advanced_tests]: Validating HugeTLB advanced [pmd_leaf_tests ]: Validating PMD leaf [pmd_huge_tests ]: Validating PMD huge [pte_savedwrite_tests ]: Validating PTE saved write [pmd_savedwrite_tests ]: Validating PMD saved write [pmd_populate_tests ]: Validating PMD populate [pte_special_tests ]: Validating PTE special [pte_protnone_tests ]: Validating PTE protnone [pmd_protnone_tests ]: Validating PMD protnone [pte_devmap_tests ]: Validating PTE devmap [pmd_devmap_tests ]: Validating PMD devmap [pte_swap_tests ]: Validating PTE swap [swap_migration_tests ]: Validating swap migration [hugetlb_basic_tests ]: Validating HugeTLB basic [pmd_thp_tests ]: Validating PMD based THP Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Vineet Gupta <vgupta@synopsys.com> [arc] Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Rapoport <rppt@kernel.org> Link: http://lkml.kernel.org/r/1593996516-7186-4-git-send-email-anshuman.khandual@arm.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Anshuman Khandual authored
This adds new tests validating for these following arch advanced page table helpers. These tests create and test specific mapping types at various page table levels. 1. pxxp_set_wrprotect() 2. pxxp_get_and_clear() 3. pxxp_set_access_flags() 4. pxxp_get_and_clear_full() 5. pxxp_test_and_clear_young() 6. pxx_leaf() 7. pxx_set_huge() 8. pxx_(clear|mk)_savedwrite() 9. huge_pxxp_xxx() [anshuman.khandual@arm.com: drop RANDOM_ORVALUE from hugetlb_advanced_tests()] Link: http://lkml.kernel.org/r/1594610587-4172-3-git-send-email-anshuman.khandual@arm.comSuggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Vineet Gupta <vgupta@synopsys.com> [arc] Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Rapoport <rppt@kernel.org> Cc: Steven Price <steven.price@arm.com> Link: http://lkml.kernel.org/r/1593996516-7186-3-git-send-email-anshuman.khandual@arm.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Anshuman Khandual authored
Patch series "mm/debug_vm_pgtable: Add some more tests", v5. This series adds some more arch page table helper validation tests which are related to core and advanced memory functions. This also creates a documentation, enlisting expected semantics for all page table helpers as suggested by Mike Rapoport previously (https://lkml.org/lkml/2020/1/30/40). There are many TRANSPARENT_HUGEPAGE and ARCH_HAS_TRANSPARENT_HUGEPAGE_PUD ifdefs scattered across the test. But consolidating all the fallback stubs is not very straight forward because ARCH_HAS_TRANSPARENT_HUGEPAGE_PUD is not explicitly dependent on ARCH_HAS_TRANSPARENT_HUGEPAGE. Tested on arm64, x86 platforms but only build tested on all other enabled platforms through ARCH_HAS_DEBUG_VM_PGTABLE i.e powerpc, arc, s390. The following failure on arm64 still exists which was mentioned previously. It will be fixed with the upcoming THP migration on arm64 enablement series. WARNING .... mm/debug_vm_pgtable.c:860 debug_vm_pgtable+0x940/0xa54 WARN_ON(!pmd_present(pmd_mkinvalid(pmd_mkhuge(pmd)))) This patch (of 4): This adds new tests validating arch page table helpers for these following core memory features. These tests create and test specific mapping types at various page table levels. 1. SPECIAL mapping 2. PROTNONE mapping 3. DEVMAP mapping 4. SOFTDIRTY mapping 5. SWAP mapping 6. MIGRATION mapping 7. HUGETLB mapping 8. THP mapping Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Vineet Gupta <vgupta@synopsys.com> [arc] Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Rapoport <rppt@kernel.org> Cc: Steven Price <steven.price@arm.com> Link: http://lkml.kernel.org/r/1594610587-4172-1-git-send-email-anshuman.khandual@arm.com Link: http://lkml.kernel.org/r/1593996516-7186-1-git-send-email-anshuman.khandual@arm.com Link: http://lkml.kernel.org/r/1593996516-7186-2-git-send-email-anshuman.khandual@arm.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Marco Elver authored
Provide the necessary KCSAN checks to assist with debugging racy use-after-frees. While KASAN is more reliable at generally catching such use-after-frees (due to its use of a quarantine), it can be difficult to debug racy use-after-frees. If a reliable reproducer exists, KCSAN can assist in debugging such issues. Note: ASSERT_EXCLUSIVE_ACCESS is a convenience wrapper if the size is simply sizeof(var). Instead, here we just use __kcsan_check_access() explicitly to pass the correct size. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Link: http://lkml.kernel.org/r/20200623072653.114563-1-elver@google.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Sebastian Andrzej Siewior authored
There is no point in using lockdep_assert_held() unlock that is about to be unlocked. It works only with lockdep and lockdep will complain if spin_unlock() is used on a lock that has not been locked. Remove superfluous lockdep_assert_held(). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Yu Zhao <yuzhao@google.com> Cc: Christopher Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20200618201234.795692-2-bigeasy@linutronix.deSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
cache_from_obj() was added by commit b9ce5ef4 ("sl[au]b: always get the cache from its page in kmem_cache_free()") to support kmemcg, where per-memcg cache can be different from the root one, so we can't use the kmem_cache pointer given to kmem_cache_free(). Prior to that commit, SLUB already had debugging check+warning that could be enabled to compare the given kmem_cache pointer to one referenced by the slab page where the object-to-be-freed resides. This check was moved to cache_from_obj(). Later the check was also enabled for SLAB_FREELIST_HARDENED configs by commit 598a0717 ("mm/slab: validate cache membership under freelist hardening"). These checks and warnings can be useful especially for the debugging, which can be improved. Commit 598a0717 changed the pr_err() with WARN_ON_ONCE() to WARN_ONCE() so only the first hit is now reported, others are silent. This patch changes it to WARN() so that all errors are reported. It's also useful to print SLUB allocation/free tracking info for the offending object, if tracking is enabled. Thus, export the SLUB print_tracking() function and provide an empty one for SLAB. For SLUB we can also benefit from the static key check in kmem_cache_debug_flags(), but we need to move this function to slab.h and declare the static key there. [1] https://lore.kernel.org/r/20200608230654.828134-18-guro@fb.com [vbabka@suse.cz: avoid bogus WARN()] Link: https://lore.kernel.org/r/20200623090213.GW5535@shao2-debian Link: http://lkml.kernel.org/r/b33e0fa7-cd28-4788-9e54-5927846329ef@suse.czSigned-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Roman Gushchin <guro@fb.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Matthew Garrett <mjg59@google.com> Cc: Jann Horn <jannh@google.com> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: Vinayak Menon <vinmenon@codeaurora.org> Link: http://lkml.kernel.org/r/afeda7ac-748b-33d8-a905-56b708148ad5@suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
The function cache_from_obj() was added by commit b9ce5ef4 ("sl[au]b: always get the cache from its page in kmem_cache_free()") to support kmemcg, where per-memcg cache can be different from the root one, so we can't use the kmem_cache pointer given to kmem_cache_free(). Prior to that commit, SLUB already had debugging check+warning that could be enabled to compare the given kmem_cache pointer to one referenced by the slab page where the object-to-be-freed resides. This check was moved to cache_from_obj(). Later the check was also enabled for SLAB_FREELIST_HARDENED configs by commit 598a0717 ("mm/slab: validate cache membership under freelist hardening"). These checks and warnings can be useful especially for the debugging, which can be improved. Commit 598a0717 changed the pr_err() with WARN_ON_ONCE() to WARN_ONCE() so only the first hit is now reported, others are silent. This patch changes it to WARN() so that all errors are reported. It's also useful to print SLUB allocation/free tracking info for the offending object, if tracking is enabled. We could export the SLUB print_tracking() function and provide an empty one for SLAB, or realize that both the debugging and hardening cases in cache_from_obj() are only supported by SLUB anyway. So this patch moves cache_from_obj() from slab.h to separate instances in slab.c and slub.c, where the SLAB version only does the kmemcg lookup and even could be completely removed once the kmemcg rework [1] is merged. The SLUB version can thus easily use the print_tracking() function. It can also use the kmem_cache_debug_flags() static key check for improved performance in kernels without the hardening and with debugging not enabled on boot. [1] https://lore.kernel.org/r/20200608230654.828134-18-guro@fb.comSigned-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Lameter <cl@linux.com> Cc: Jann Horn <jannh@google.com> Cc: Kees Cook <keescook@chromium.org> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Link: http://lkml.kernel.org/r/20200610163135.17364-10-vbabka@suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
There are few more places in SLUB that could benefit from reduced overhead of the static key introduced by a previous patch: - setup_object_debug() called on each object in newly allocated slab page - setup_page_debug() called on newly allocated slab page - __free_slab() called on freed slab page Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Roman Gushchin <guro@fb.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Jann Horn <jannh@google.com> Cc: Kees Cook <keescook@chromium.org> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Link: http://lkml.kernel.org/r/20200610163135.17364-9-vbabka@suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
There are few places that call kmem_cache_debug(s) (which tests if any of debug flags are enabled for a cache) immediately followed by a test for a specific flag. The compiler can probably eliminate the extra check, but we can make the code nicer by introducing kmem_cache_debug_flags() that works like kmem_cache_debug() (including the static key check) but tests for specific flag(s). The next patches will add more users. [vbabka@suse.cz: change return from int to bool, per Kees. Add VM_WARN_ON_ONCE() for invalid flags, per Roman] Link: http://lkml.kernel.org/r/949b90ed-e0f0-07d7-4d21-e30ec0958a7c@suse.czSigned-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Roman Gushchin <guro@fb.com> Acked-by: Christoph Lameter <cl@linux.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Jann Horn <jannh@google.com> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Link: http://lkml.kernel.org/r/20200610163135.17364-8-vbabka@suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
One advantage of CONFIG_SLUB_DEBUG is that a generic distro kernel can be built with the option enabled, but it's inactive until simply enabled on boot, without rebuilding the kernel. With a static key, we can further eliminate the overhead of checking whether a cache has a particular debug flag enabled if we know that there are no such caches (slub_debug was not enabled during boot). We use the same mechanism also for e.g. page_owner, debug_pagealloc or kmemcg functionality. This patch introduces the static key and makes the general check for per-cache debug flags kmem_cache_debug() use it. This benefits several call sites, including (slow path but still rather frequent) __slab_free(). The next patches will add more uses. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Roman Gushchin <guro@fb.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Jann Horn <jannh@google.com> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Link: http://lkml.kernel.org/r/20200610163135.17364-7-vbabka@suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
The attribute reflects the SLAB_RECLAIM_ACCOUNT cache flag. It's not clear why this attribute was writable in the first place, as it's tied to how the cache is used by its creator, it's not a user tunable. Furthermore: - it affects slab merging, but that's not being checked while toggled - if affects whether __GFP_RECLAIMABLE flag is used to allocate page, but the runtime toggle doesn't update allocflags - it affects cache_vmstat_idx() so runtime toggling might lead to incosistency of NR_SLAB_RECLAIMABLE and NR_SLAB_UNRECLAIMABLE Thus make it read-only. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Roman Gushchin <guro@fb.com> Cc: Christoph Lameter <cl@linux.com> Cc: Jann Horn <jannh@google.com> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Link: http://lkml.kernel.org/r/20200610163135.17364-6-vbabka@suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
SLUB_DEBUG creates several files under /sys/kernel/slab/<cache>/ that can be read to check if the respective debugging options are enabled for given cache. Some options, namely sanity_checks, trace, and failslab can be also enabled and disabled at runtime by writing into the files. The runtime toggling is racy. Some options disable __CMPXCHG_DOUBLE when enabled, which means that in case of concurrent allocations, some can still use __CMPXCHG_DOUBLE and some not, leading to potential corruption. The s->flags field is also not updated or checked atomically. The simplest solution is to remove the runtime toggling. The extended slub_debug boot parameter syntax introduced by earlier patch should allow to fine-tune the debugging configuration during boot with same granularity. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Roman Gushchin <guro@fb.com> Cc: Christoph Lameter <cl@linux.com> Cc: Jann Horn <jannh@google.com> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Link: http://lkml.kernel.org/r/20200610163135.17364-5-vbabka@suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
SLUB allows runtime changing of page allocation order by writing into the /sys/kernel/slab/<cache>/order file. Jann has reported [1] that this interface allows the order to be set too small, leading to crashes. While it's possible to fix the immediate issue, closer inspection reveals potential races. Storing the new order calls calculate_sizes() which non-atomically updates a lot of kmem_cache fields while the cache is still in use. Unexpected behavior might occur even if the fields are set to the same value as they were. This could be fixed by splitting out the part of calculate_sizes() that depends on forced_order, so that we only update kmem_cache.oo field. This could still race with init_cache_random_seq(), shuffle_freelist(), allocate_slab(). Perhaps it's possible to audit and e.g. add some READ_ONCE/WRITE_ONCE accesses, it might be easier just to remove the runtime order changes, which is what this patch does. If there are valid usecases for per-cache order setting, we could e.g. extend the boot parameters to do that. [1] https://lore.kernel.org/r/CAG48ez31PP--h6_FzVyfJ4H86QYczAFPdxtJHUEEan+7VJETAQ@mail.gmail.comReported-by: Jann Horn <jannh@google.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Christoph Lameter <cl@linux.com> Acked-by: Roman Gushchin <guro@fb.com> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Link: http://lkml.kernel.org/r/20200610163135.17364-4-vbabka@suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
SLUB_DEBUG creates several files under /sys/kernel/slab/<cache>/ that can be read to check if the respective debugging options are enabled for given cache. The options can be also toggled at runtime by writing into the files. Some of those, namely red_zone, poison, and store_user can be toggled only when no objects yet exist in the cache. Vijayanand reports [1] that there is a problem with freelist randomization if changing the debugging option's state results in different number of objects per page, and the random sequence cache needs thus needs to be recomputed. However, another problem is that the check for "no objects yet exist in the cache" is racy, as noted by Jann [2] and fixing that would add overhead or otherwise complicate the allocation/freeing paths. Thus it would be much simpler just to remove the runtime toggling support. The documentation describes it's "In case you forgot to enable debugging on the kernel command line", but the neccessity of having no objects limits its usefulness anyway for many caches. Vijayanand describes an use case [3] where debugging is enabled for all but zram caches for memory overhead reasons, and using the runtime toggles was the only way to achieve such configuration. After the previous patch it's now possible to do that directly from the kernel boot option, so we can remove the dangerous runtime toggles by making the /sys attribute files read-only. While updating it, also improve the documentation of the debugging /sys files. [1] https://lkml.kernel.org/r/1580379523-32272-1-git-send-email-vjitta@codeaurora.org [2] https://lore.kernel.org/r/CAG48ez31PP--h6_FzVyfJ4H86QYczAFPdxtJHUEEan+7VJETAQ@mail.gmail.com [3] https://lore.kernel.org/r/1383cd32-1ddc-4dac-b5f8-9c42282fa81c@codeaurora.orgReported-by: Vijayanand Jitta <vjitta@codeaurora.org> Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Roman Gushchin <guro@fb.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Link: http://lkml.kernel.org/r/20200610163135.17364-3-vbabka@suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
Patch series "slub_debug fixes and improvements". The slub_debug kernel boot parameter can either apply a single set of options to all caches or a list of caches. There is a use case where debugging is applied for all caches and then disabled at runtime for specific caches, for performance and memory consumption reasons [1]. As runtime changes are dangerous, extend the boot parameter syntax so that multiple blocks of either global or slab-specific options can be specified, with blocks delimited by ';'. This will also support the use case of [1] without runtime changes. For details see the updated Documentation/vm/slub.rst [1] https://lore.kernel.org/r/1383cd32-1ddc-4dac-b5f8-9c42282fa81c@codeaurora.org [weiyongjun1@huawei.com: make parse_slub_debug_flags() static] Link: http://lkml.kernel.org/r/20200702150522.4940-1-weiyongjun1@huawei.comSigned-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: Jann Horn <jannh@google.com> Cc: Roman Gushchin <guro@fb.com> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Link: http://lkml.kernel.org/r/20200610163135.17364-2-vbabka@suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Xiao Yang authored
kmem_list3 has been renamed to kmem_cache_node long long ago so update it. References: 6744f087 ("slab: Common name for the per node structures") ce8eb6c4 ("slab: Rename list3/l3 to node") Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Pekka Enberg <penberg@kernel.org> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Link: http://lkml.kernel.org/r/20200722033355.26908-1-yangx.jy@cn.fujitsu.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Long Li authored
kmalloc cannot allocate memory from HIGHMEM. Allocating large amounts of memory currently bypasses the check and will simply leak the memory when page_address() returns NULL. To fix this, factor the GFP_SLAB_BUG_MASK check out of slab & slub, and call it from kmalloc_order() as well. In order to make the code clear, the warning message is put in one place. Signed-off-by: Long Li <lonuxli.64@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Pekka Enberg <penberg@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Link: http://lkml.kernel.org/r/20200704035027.GA62481@lilongSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Kees Cook authored
Similar to commit ce6fa91b ("mm/slub.c: add a naive detection of double free or corruption"), add a very cheap double-free check for SLAB under CONFIG_SLAB_FREELIST_HARDENED. With this added, the "SLAB_FREE_DOUBLE" LKDTM test passes under SLAB: lkdtm: Performing direct entry SLAB_FREE_DOUBLE lkdtm: Attempting double slab free ... ------------[ cut here ]------------ WARNING: CPU: 2 PID: 2193 at mm/slab.c:757 ___cache _free+0x325/0x390 [keescook@chromium.org: fix misplaced __free_one()] Link: http://lkml.kernel.org/r/202006261306.0D82A2B@keescook Link: https://lore.kernel.org/lkml/7ff248c7-d447-340c-a8e2-8c02972aca70@infradead.orgSigned-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Randy Dunlap <rdunlap@infradead.org> [build tested] Cc: Roman Gushchin <guro@fb.com> Cc: Christoph Lameter <cl@linux.com> Cc: Alexander Popov <alex.popov@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Vinayak Menon <vinmenon@codeaurora.org> Cc: Matthew Garrett <mjg59@google.com> Cc: Jann Horn <jannh@google.com> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Link: http://lkml.kernel.org/r/20200625215548.389774-3-keescook@chromium.orgSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Kees Cook authored
Patch series "mm: Expand CONFIG_SLAB_FREELIST_HARDENED to include SLAB" In reviewing Vlastimil Babka's latest slub debug series, I realized[1] that several checks under CONFIG_SLAB_FREELIST_HARDENED weren't being applied to SLAB. Fix this by expanding the Kconfig coverage, and adding a simple double-free test for SLAB. This patch (of 2): Include SLAB caches when performing kmem_cache pointer verification. A defense against such corruption[1] should be applied to all the allocators. With this added, the "SLAB_FREE_CROSS" and "SLAB_FREE_PAGE" LKDTM tests now pass on SLAB: lkdtm: Performing direct entry SLAB_FREE_CROSS lkdtm: Attempting cross-cache slab free ... ------------[ cut here ]------------ cache_from_obj: Wrong slab cache. lkdtm-heap-b but object is from lkdtm-heap-a WARNING: CPU: 2 PID: 2195 at mm/slab.h:530 kmem_cache_free+0x8d/0x1d0 ... lkdtm: Performing direct entry SLAB_FREE_PAGE lkdtm: Attempting non-Slab slab free ... ------------[ cut here ]------------ virt_to_cache: Object is not a Slab page! WARNING: CPU: 1 PID: 2202 at mm/slab.h:489 kmem_cache_free+0x196/0x1d0 Additionally clean up neighboring Kconfig entries for clarity, readability, and redundant option removal. [1] https://github.com/ThomasKing2014/slides/raw/master/Building%20universal%20Android%20rooting%20with%20a%20type%20confusion%20vulnerability.pdf Fixes: 598a0717 ("mm/slab: validate cache membership under freelist hardening") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Alexander Popov <alex.popov@linux.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Jann Horn <jannh@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Matthew Garrett <mjg59@google.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Roman Gushchin <guro@fb.com> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: Vinayak Menon <vinmenon@codeaurora.org> Link: http://lkml.kernel.org/r/20200625215548.389774-1-keescook@chromium.org Link: http://lkml.kernel.org/r/20200625215548.389774-2-keescook@chromium.orgSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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William Kucharski authored
Other mm routines such as kfree() and kzfree() silently do the right thing if passed a NULL pointer, so ksize() should do the same. Signed-off-by: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Link: http://lkml.kernel.org/r/20200616225409.4670-1-william.kucharski@oracle.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Waiman Long authored
As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Pavel Machek authored
Based on what fails, function can return with nfs_sync_rwlock either locked or unlocked. That can not be right. Always return with lock unlocked on error. Fixes: 4cd9973f ("ocfs2: avoid inode removal while nfsd is accessing it") Signed-off-by: Pavel Machek (CIP) <pavel@denx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Link: http://lkml.kernel.org/r/20200724124443.GA28164@duo.ucw.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Alexander A. Klimov authored
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `xmlns`: For each link, `http://[^# ]*(?:\w|/)`: If neither `gnu\.org/license`, nor `mozilla\.org/MPL`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Link: http://lkml.kernel.org/r/20200713174456.36596-1-grandmaster@al2klimov.deSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Junxiao Bi authored
Dan Carpenter reported the following static checker warning. fs/ocfs2/super.c:1269 ocfs2_parse_options() warn: '(-1)' 65535 can't fit into 32767 'mopt->slot' fs/ocfs2/suballoc.c:859 ocfs2_init_inode_steal_slot() warn: '(-1)' 65535 can't fit into 32767 'osb->s_inode_steal_slot' fs/ocfs2/suballoc.c:867 ocfs2_init_meta_steal_slot() warn: '(-1)' 65535 can't fit into 32767 'osb->s_meta_steal_slot' That's because OCFS2_INVALID_SLOT is (u16)-1. Slot number in ocfs2 can be never negative, so change s16 to u16. Fixes: 9277f833 ("ocfs2: fix value of OCFS2_INVALID_SLOT") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Reviewed-by: Gang He <ghe@suse.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200627001259.19757-1-junxiao.bi@oracle.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Randy Dunlap authored
Drop the repeated word "is" in a comment. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Link: http://lkml.kernel.org/r/20200720001421.28823-1-rdunlap@infradead.orgSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Gang He authored
When use setfacl command to change a file's acl, the user cannot get the latest acl information from the file via getfacl command, until remounting the file system. e.g. setfacl -m u:ivan:rw /ocfs2/ivan getfacl /ocfs2/ivan getfacl: Removing leading '/' from absolute path names file: ocfs2/ivan owner: root group: root user::rw- group::r-- mask::r-- other::r-- The latest acl record("u:ivan:rw") cannot be returned via getfacl command until remounting. Signed-off-by: Gang He <ghe@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Jun Piao <piaojun@huawei.com> Link: http://lkml.kernel.org/r/20200717023751.9922-1-ghe@suse.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Luca Stefani authored
Clang's Control Flow Integrity (CFI) is a security mechanism that can help prevent JOP chains, deployed extensively in downstream kernels used in Android. Its deployment is hindered by mismatches in function signatures. For this case, we make callbacks match their intended function signature, and cast parameters within them rather than casting the callback when passed as a parameter. When running `mount -t ntfs ...` we observe the following trace: Call trace: __cfi_check_fail+0x1c/0x24 name_to_dev_t+0x0/0x404 iget5_locked+0x594/0x5e8 ntfs_fill_super+0xbfc/0x43ec mount_bdev+0x30c/0x3cc ntfs_mount+0x18/0x24 mount_fs+0x1b0/0x380 vfs_kern_mount+0x90/0x398 do_mount+0x5d8/0x1a10 SyS_mount+0x108/0x144 el0_svc_naked+0x34/0x38 Signed-off-by: Luca Stefani <luca.stefani.ge1@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: freak07 <michalechner92@googlemail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Anton Altaparmakov <anton@tuxera.com> Link: http://lkml.kernel.org/r/20200718112513.533800-1-luca.stefani.ge1@gmail.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Colin Ian King authored
Here are some of the more common spelling mistakes and typos that I've found while fixing up spelling mistakes in the kernel since April 2020. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20200714092837.173796-1-colin.king@canonical.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joe Perches authored
Add regulator_ops to expected to be const list. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Pi-Hsun Shih <pihsun@chromium.org> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Mark Brown <broonie@kernel.org> Cc: Benson Leung <bleung@chromium.org> Cc: Enric Balletbo i Serra <enric.balletbo@collabora.com> Cc: Guenter Roeck <groeck@chromium.org> Cc: Rikard Falkeborn <rikard.falkeborn@gmail.com> Link: http://lkml.kernel.org/r/dab1ba1aa03a8236933cfb7a28937efb0b808f13.camel@perches.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Konstantin Khlebnikov authored
Add option decode_stacktrace -r <release> to specify only release name. This is enough to guess standard paths to vmlinux and modules: $ echo -e 'schedule+0x0/0x0 tap_open+0x0/0x0 [tap]' | ./scripts/decode_stacktrace.sh -r 5.4.0-37-generic schedule (kernel/sched/core.c:4138) tap_open (drivers/net/tap.c:502) tap Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Sasha Levin <sashal@kernel.org> Link: http://lkml.kernel.org/r/159282923334.248444.2399153100007347838.stgit@buzzSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Konstantin Khlebnikov authored
Try to find module in directory with vmlinux (for fresh build). Then try standard paths where debuginfo are usually placed. Pick first file which have elf section '.debug_line'. Before: $ echo 'tap_open+0x0/0x0 [tap]' | ./scripts/decode_stacktrace.sh /usr/lib/debug/boot/vmlinux-5.4.0-37-generic WARNING! Modules path isn't set, but is needed to parse this symbol tap_open+0x0/0x0 tap After: $ echo 'tap_open+0x0/0x0 [tap]' | ./scripts/decode_stacktrace.sh /usr/lib/debug/boot/vmlinux-5.4.0-37-generic tap_open (drivers/net/tap.c:502) tap Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Sasha Levin <sashal@kernel.org> Link: http://lkml.kernel.org/r/159282923068.248444.5461337458421616083.stgit@buzzSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Konstantin Khlebnikov authored
Guess path to kernel sources using known location of symbol "kernel_init". Make basepath argument optional. Before: $ echo 'vfs_open+0x0/0x0' | ./scripts/decode_stacktrace.sh vmlinux "" vfs_open (home/khlebnikov/src/linux/fs/open.c:912) After: $ echo 'vfs_open+0x0/0x0' | ./scripts/decode_stacktrace.sh vmlinux vfs_open (fs/open.c:912) Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Sasha Levin <sashal@kernel.org> Link: http://lkml.kernel.org/r/159282922803.248444.2379229451667913634.stgit@buzzSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Konstantin Khlebnikov authored
For now script turns missing symbols into '0' and make bogus decode. Skip them instead. Also simplify parsing output of 'nm'. Before: $ echo 'xxx+0x0/0x0' | ./scripts/decode_stacktrace.sh vmlinux "" xxx (home/khlebnikov/src/linux/./arch/x86/include/asm/processor.h:398) After: $ echo 'xxx+0x0/0x0' | ./scripts/decode_stacktrace.sh vmlinux "" xxx+0x0/0x0 Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Sasha Levin <sashal@kernel.org> Link: http://lkml.kernel.org/r/159282922499.248444.4883465570858385250.stgit@buzzSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Nikolay Borisov authored
Library archives (.a) usually contain multiple object files so their output of nm --size-sort contains lines like: <omitted for brevity> 00000000000003a8 t run_test extent-map-tests.o: <omitted for brevity> bloat-o-meter currently doesn't handle them which results in errors when calling .split() on them. Fix this by simply ignoring them. This enables diffing subsystems which generate built-in.a files. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20200603103513.3712-1-nborisov@suse.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jialu Xu authored
Parse compiled source from *.cmd but don't 'find' too many files that are not related to compilation. [xujialu@vimux.org: don't expand symlinks by add option -s for realpath] Link: http://lkml.kernel.org/r/5efc5bfb.1c69fb81.41bf5.7131SMTPIN_ADDED_MISSING@mx.google.comSigned-off-by: Jialu Xu <xujialu@vimux.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Joe Perches <joe@perches.com> Link: http://lkml.kernel.org/r/5ee5d8e3.1c69fb81.9b804.47b2SMTPIN_ADDED_MISSING@mx.google.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Gaurav Singh authored
Haven't reproduced this issue. This PR is does a minor code cleanup. Signed-off-by: Gaurav Singh <gaurav1086@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Michal Koutn <mkoutny@suse.com> Cc: Roman Gushchin <guro@fb.com> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Chris Down <chris@chrisdown.name> Link: http://lkml.kernel.org/r/20200726013808.22242-1-gaurav1086@gmail.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Alexander A. Klimov authored
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20200726120752.16768-1-grandmaster@al2klimov.deSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Ilias Stamatis authored
Originally kthread_create_on_cpu() parked and woke up the new thread. However, since commit a65d4096 ("kthread/smpboot: do not park in kthread_create_on_cpu()") this is no longer the case. This patch removes the comment that has been left behind and is now incorrect / stale. Fixes: a65d4096 ("kthread/smpboot: do not park in kthread_create_on_cpu()") Signed-off-by: Ilias Stamatis <stamatis.iliass@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: http://lkml.kernel.org/r/20200611135920.240551-1-stamatis.iliass@gmail.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Peter Zijlstra authored
For SMP systems using IPI based TLB invalidation, looking at current->active_mm is entirely reasonable. This then presents the following race condition: CPU0 CPU1 flush_tlb_mm(mm) use_mm(mm) <send-IPI> tsk->active_mm = mm; <IPI> if (tsk->active_mm == mm) // flush TLBs </IPI> switch_mm(old_mm,mm,tsk); Where it is possible the IPI flushed the TLBs for @old_mm, not @mm, because the IPI lands before we actually switched. Avoid this by disabling IRQs across changing ->active_mm and switch_mm(). Of the (SMP) architectures that have IPI based TLB invalidate: Alpha - checks active_mm ARC - ASID specific IA64 - checks active_mm MIPS - ASID specific flush OpenRISC - shoots down world PARISC - shoots down world SH - ASID specific SPARC - ASID specific x86 - N/A xtensa - checks active_mm So at the very least Alpha, IA64 and Xtensa are suspect. On top of this, for scheduler consistency we need at least preemption disabled across changing tsk->mm and doing switch_mm(), which is currently provided by task_lock(), but that's not sufficient for PREEMPT_RT. [akpm@linux-foundation.org: add comment] Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Kees Cook <keescook@chromium.org> Cc: Jann Horn <jannh@google.com> Cc: Will Deacon <will@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200721154106.GE10769@hirez.programming.kicks-ass.netSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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