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2021-03-13ia64: fix ptrace(PTRACE_SYSCALL_INFO_EXIT) signSergei Trofimovich1-1/+1
In https://bugs.gentoo.org/769614 Dmitry noticed that `ptrace(PTRACE_GET_SYSCALL_INFO)` does not return error sign properly. The bug is in mismatch between get/set errors: static inline long syscall_get_error(struct task_struct *task, struct pt_regs *regs) { return regs->r10 == -1 ? regs->r8:0; } static inline long syscall_get_return_value(struct task_struct *task, struct pt_regs *regs) { return regs->r8; } static inline void syscall_set_return_value(struct task_struct *task, struct pt_regs *regs, int error, long val) { if (error) { /* error < 0, but ia64 uses > 0 return value */ regs->r8 = -error; regs->r10 = -1; } else { regs->r8 = val; regs->r10 = 0; } } Tested on v5.10 on rx3600 machine (ia64 9040 CPU). Link: https://lkml.kernel.org/r/20210221002554.333076-2-slyfox@gentoo.org Link: https://bugs.gentoo.org/769614 Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> Reported-by: Dmitry V. Levin <ldv@altlinux.org> Reviewed-by: Dmitry V. Levin <ldv@altlinux.org> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13ia64: fix ia64_syscall_get_set_arguments() for break-based syscallsSergei Trofimovich1-6/+18
In https://bugs.gentoo.org/769614 Dmitry noticed that `ptrace(PTRACE_GET_SYSCALL_INFO)` does not work for syscalls called via glibc's syscall() wrapper. ia64 has two ways to call syscalls from userspace: via `break` and via `eps` instructions. The difference is in stack layout: 1. `eps` creates simple stack frame: no locals, in{0..7} == out{0..8} 2. `break` uses userspace stack frame: may be locals (glibc provides one), in{0..7} == out{0..8}. Both work fine in syscall handling cde itself. But `ptrace(PTRACE_GET_SYSCALL_INFO)` uses unwind mechanism to re-extract syscall arguments but it does not account for locals. The change always skips locals registers. It should not change `eps` path as kernel's handler already enforces locals=0 and fixes `break`. Tested on v5.10 on rx3600 machine (ia64 9040 CPU). Link: https://lkml.kernel.org/r/20210221002554.333076-1-slyfox@gentoo.org Link: https://bugs.gentoo.org/769614 Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> Reported-by: Dmitry V. Levin <ldv@altlinux.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm/userfaultfd: fix memory corruption due to writeprotectNadav Amit1-0/+8
Userfaultfd self-test fails occasionally, indicating a memory corruption. Analyzing this problem indicates that there is a real bug since mmap_lock is only taken for read in mwriteprotect_range() and defers flushes, and since there is insufficient consideration of concurrent deferred TLB flushes in wp_page_copy(). Although the PTE is flushed from the TLBs in wp_page_copy(), this flush takes place after the copy has already been performed, and therefore changes of the page are possible between the time of the copy and the time in which the PTE is flushed. To make matters worse, memory-unprotection using userfaultfd also poses a problem. Although memory unprotection is logically a promotion of PTE permissions, and therefore should not require a TLB flush, the current userrfaultfd code might actually cause a demotion of the architectural PTE permission: when userfaultfd_writeprotect() unprotects memory region, it unintentionally *clears* the RW-bit if it was already set. Note that this unprotecting a PTE that is not write-protected is a valid use-case: the userfaultfd monitor might ask to unprotect a region that holds both write-protected and write-unprotected PTEs. The scenario that happens in selftests/vm/userfaultfd is as follows: cpu0 cpu1 cpu2 ---- ---- ---- [ Writable PTE cached in TLB ] userfaultfd_writeprotect() [ write-*unprotect* ] mwriteprotect_range() mmap_read_lock() change_protection() change_protection_range() ... change_pte_range() [ *clear* “write”-bit ] [ defer TLB flushes ] [ page-fault ] ... wp_page_copy() cow_user_page() [ copy page ] [ write to old page ] ... set_pte_at_notify() A similar scenario can happen: cpu0 cpu1 cpu2 cpu3 ---- ---- ---- ---- [ Writable PTE cached in TLB ] userfaultfd_writeprotect() [ write-protect ] [ deferred TLB flush ] userfaultfd_writeprotect() [ write-unprotect ] [ deferred TLB flush] [ page-fault ] wp_page_copy() cow_user_page() [ copy page ] ... [ write to page ] set_pte_at_notify() This race exists since commit 292924b26024 ("userfaultfd: wp: apply _PAGE_UFFD_WP bit"). Yet, as Yu Zhao pointed, these races became apparent since commit 09854ba94c6a ("mm: do_wp_page() simplification") which made wp_page_copy() more likely to take place, specifically if page_count(page) > 1. To resolve the aforementioned races, check whether there are pending flushes on uffd-write-protected VMAs, and if there are, perform a flush before doing the COW. Further optimizations will follow to avoid during uffd-write-unprotect unnecassary PTE write-protection and TLB flushes. Link: https://lkml.kernel.org/r/20210304095423.3825684-1-namit@vmware.com Fixes: 09854ba94c6a ("mm: do_wp_page() simplification") Signed-off-by: Nadav Amit <namit@vmware.com> Suggested-by: Yu Zhao <yuzhao@google.com> Reviewed-by: Peter Xu <peterx@redhat.com> Tested-by: Peter Xu <peterx@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Pavel Emelyanov <xemul@openvz.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Will Deacon <will@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> [5.9+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13kasan: fix KASAN_STACK dependency for HW_TAGSAndrey Konovalov1-0/+1
There's a runtime failure when running HW_TAGS-enabled kernel built with GCC on hardware that doesn't support MTE. GCC-built kernels always have CONFIG_KASAN_STACK enabled, even though stack instrumentation isn't supported by HW_TAGS. Having that config enabled causes KASAN to issue MTE-only instructions to unpoison kernel stacks, which causes the failure. Fix the issue by disallowing CONFIG_KASAN_STACK when HW_TAGS is used. (The commit that introduced CONFIG_KASAN_HW_TAGS specified proper dependency for CONFIG_KASAN_STACK_ENABLE but not for CONFIG_KASAN_STACK.) Link: https://lkml.kernel.org/r/59e75426241dbb5611277758c8d4d6f5f9298dac.1615215441.git.andreyknvl@google.com Fixes: 6a63a63ff1ac ("kasan: introduce CONFIG_KASAN_HW_TAGS") Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reported-by: Catalin Marinas <catalin.marinas@arm.com> Cc: <stable@vger.kernel.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Marco Elver <elver@google.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13kasan, mm: fix crash with HW_TAGS and DEBUG_PAGEALLOCAndrey Konovalov1-2/+6
Currently, kasan_free_nondeferred_pages()->kasan_free_pages() is called after debug_pagealloc_unmap_pages(). This causes a crash when debug_pagealloc is enabled, as HW_TAGS KASAN can't set tags on an unmapped page. This patch puts kasan_free_nondeferred_pages() before debug_pagealloc_unmap_pages() and arch_free_page(), which can also make the page unavailable. Link: https://lkml.kernel.org/r/24cd7db274090f0e5bc3adcdc7399243668e3171.1614987311.git.andreyknvl@google.com Fixes: 94ab5b61ee16 ("kasan, arm64: enable CONFIG_KASAN_HW_TAGS") Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Marco Elver <elver@google.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm/madvise: replace ptrace attach requirement for process_madviseSuren Baghdasaryan1-1/+12
process_madvise currently requires ptrace attach capability. PTRACE_MODE_ATTACH gives one process complete control over another process. It effectively removes the security boundary between the two processes (in one direction). Granting ptrace attach capability even to a system process is considered dangerous since it creates an attack surface. This severely limits the usage of this API. The operations process_madvise can perform do not affect the correctness of the operation of the target process; they only affect where the data is physically located (and therefore, how fast it can be accessed). What we want is the ability for one process to influence another process in order to optimize performance across the entire system while leaving the security boundary intact. Replace PTRACE_MODE_ATTACH with a combination of PTRACE_MODE_READ and CAP_SYS_NICE. PTRACE_MODE_READ to prevent leaking ASLR metadata and CAP_SYS_NICE for influencing process performance. Link: https://lkml.kernel.org/r/20210303185807.2160264-1-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Jann Horn <jannh@google.com> Cc: Jeff Vander Stoep <jeffv@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tim Murray <timmurray@google.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: <stable@vger.kernel.org> [5.10+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13include/linux/sched/mm.h: use rcu_dereference in in_vfork()Matthew Wilcox (Oracle)1-1/+2
Fix a sparse warning by using rcu_dereference(). Technically this is a bug and a sufficiently aggressive compiler could reload the `real_parent' pointer outside the protection of the rcu lock (and access freed memory), but I think it's pretty unlikely to happen. Link: https://lkml.kernel.org/r/20210221194207.1351703-1-willy@infradead.org Fixes: b18dc5f291c0 ("mm, oom: skip vforked tasks from being selected") Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13kfence: fix reports if constant function prefixes existMarco Elver1-6/+12
Some architectures prefix all functions with a constant string ('.' on ppc64). Add ARCH_FUNC_PREFIX, which may optionally be defined in <asm/kfence.h>, so that get_stack_skipnr() can work properly. Link: https://lkml.kernel.org/r/f036c53d-7e81-763c-47f4-6024c6c5f058@csgroup.eu Link: https://lkml.kernel.org/r/20210304144000.1148590-1-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu> Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13kfence, slab: fix cache_alloc_debugcheck_after() for bulk allocationsMarco Elver1-1/+1
cache_alloc_debugcheck_after() performs checks on an object, including adjusting the returned pointer. None of this should apply to KFENCE objects. While for non-bulk allocations, the checks are skipped when we allocate via KFENCE, for bulk allocations cache_alloc_debugcheck_after() is called via cache_alloc_debugcheck_after_bulk(). Fix it by skipping cache_alloc_debugcheck_after() for KFENCE objects. Link: https://lkml.kernel.org/r/20210304205256.2162309-1-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13kfence: fix printk format for ptrdiff_tMarco Elver1-6/+6
Use %td for ptrdiff_t. Link: https://lkml.kernel.org/r/3abbe4c9-16ad-c168-a90f-087978ccd8f7@csgroup.eu Link: https://lkml.kernel.org/r/20210303121157.3430807-1-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Alexander Potapenko <glider@google.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Jann Horn <jannh@google.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13linux/compiler-clang.h: define HAVE_BUILTIN_BSWAP*Arnd Bergmann1-0/+6
Separating compiler-clang.h from compiler-gcc.h inadventently dropped the definitions of the three HAVE_BUILTIN_BSWAP macros, which requires falling back to the open-coded version and hoping that the compiler detects it. Since all versions of clang support the __builtin_bswap interfaces, add back the flags and have the headers pick these up automatically. This results in a 4% improvement of compilation speed for arm defconfig. Note: it might also be worth revisiting which architectures set CONFIG_ARCH_USE_BUILTIN_BSWAP for one compiler or the other, today this is set on six architectures (arm32, csky, mips, powerpc, s390, x86), while another ten architectures define custom helpers (alpha, arc, ia64, m68k, mips, nios2, parisc, sh, sparc, xtensa), and the rest (arm64, h8300, hexagon, microblaze, nds32, openrisc, riscv) just get the unoptimized version and rely on the compiler to detect it. A long time ago, the compiler builtins were architecture specific, but nowadays, all compilers that are able to build the kernel have correct implementations of them, though some may not be as optimized as the inline asm versions. The patch that dropped the optimization landed in v4.19, so as discussed it would be fairly safe to backport this revert to stable kernels to the 4.19/5.4/5.10 stable kernels, but there is a remaining risk for regressions, and it has no known side-effects besides compile speed. Link: https://lkml.kernel.org/r/20210226161151.2629097-1-arnd@kernel.org Link: https://lore.kernel.org/lkml/20210225164513.3667778-1-arnd@kernel.org/ Fixes: 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Miguel Ojeda <ojeda@kernel.org> Acked-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Nick Hu <nickhu@andestech.com> Cc: Greentime Hu <green.hu@gmail.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Guo Ren <guoren@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Sami Tolvanen <samitolvanen@google.com> Cc: Marco Elver <elver@google.com> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13MAINTAINERS: exclude uapi directories in API/ABI sectionVlastimil Babka1-2/+2
Commit 7b4693e644cb ("MAINTAINERS: add uapi directories to API/ABI section") added include/uapi/ and arch/*/include/uapi/ so that patches modifying them CC linux-api. However that was already done in the past and resulted in too much noise and thus later removed, as explained in b14fd334ff3d ("MAINTAINERS: trim the file triggers for ABI/API") To prevent another round of addition and removal in the future, change the entries to X: (explicit exclusion) for documentation purposes, although they are not subdirectories of broader included directories, as there is apparently no defined way to add plain comments in subsystem sections. Link: https://lkml.kernel.org/r/20210301100255.25229-1-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com> Acked-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13binfmt_misc: fix possible deadlock in bm_register_writeLior Ribak1-15/+14
There is a deadlock in bm_register_write: First, in the begining of the function, a lock is taken on the binfmt_misc root inode with inode_lock(d_inode(root)). Then, if the user used the MISC_FMT_OPEN_FILE flag, the function will call open_exec on the user-provided interpreter. open_exec will call a path lookup, and if the path lookup process includes the root of binfmt_misc, it will try to take a shared lock on its inode again, but it is already locked, and the code will get stuck in a deadlock To reproduce the bug: $ echo ":iiiii:E::ii::/proc/sys/fs/binfmt_misc/bla:F" > /proc/sys/fs/binfmt_misc/register backtrace of where the lock occurs (#5): 0 schedule () at ./arch/x86/include/asm/current.h:15 1 0xffffffff81b51237 in rwsem_down_read_slowpath (sem=0xffff888003b202e0, count=<optimized out>, state=state@entry=2) at kernel/locking/rwsem.c:992 2 0xffffffff81b5150a in __down_read_common (state=2, sem=<optimized out>) at kernel/locking/rwsem.c:1213 3 __down_read (sem=<optimized out>) at kernel/locking/rwsem.c:1222 4 down_read (sem=<optimized out>) at kernel/locking/rwsem.c:1355 5 0xffffffff811ee22a in inode_lock_shared (inode=<optimized out>) at ./include/linux/fs.h:783 6 open_last_lookups (op=0xffffc9000022fe34, file=0xffff888004098600, nd=0xffffc9000022fd10) at fs/namei.c:3177 7 path_openat (nd=nd@entry=0xffffc9000022fd10, op=op@entry=0xffffc9000022fe34, flags=flags@entry=65) at fs/namei.c:3366 8 0xffffffff811efe1c in do_filp_open (dfd=<optimized out>, pathname=pathname@entry=0xffff8880031b9000, op=op@entry=0xffffc9000022fe34) at fs/namei.c:3396 9 0xffffffff811e493f in do_open_execat (fd=fd@entry=-100, name=name@entry=0xffff8880031b9000, flags=<optimized out>, flags@entry=0) at fs/exec.c:913 10 0xffffffff811e4a92 in open_exec (name=<optimized out>) at fs/exec.c:948 11 0xffffffff8124aa84 in bm_register_write (file=<optimized out>, buffer=<optimized out>, count=19, ppos=<optimized out>) at fs/binfmt_misc.c:682 12 0xffffffff811decd2 in vfs_write (file=file@entry=0xffff888004098500, buf=buf@entry=0xa758d0 ":iiiii:E::ii::i:CF ", count=count@entry=19, pos=pos@entry=0xffffc9000022ff10) at fs/read_write.c:603 13 0xffffffff811defda in ksys_write (fd=<optimized out>, buf=0xa758d0 ":iiiii:E::ii::i:CF ", count=19) at fs/read_write.c:658 14 0xffffffff81b49813 in do_syscall_64 (nr=<optimized out>, regs=0xffffc9000022ff58) at arch/x86/entry/common.c:46 15 0xffffffff81c0007c in entry_SYSCALL_64 () at arch/x86/entry/entry_64.S:120 To solve the issue, the open_exec call is moved to before the write lock is taken by bm_register_write Link: https://lkml.kernel.org/r/20210228224414.95962-1-liorribak@gmail.com Fixes: 948b701a607f1 ("binfmt_misc: add persistent opened binary handler for containers") Signed-off-by: Lior Ribak <liorribak@gmail.com> Acked-by: Helge Deller <deller@gmx.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm/highmem.c: fix zero_user_segments() with start > endOGAWA Hirofumi1-5/+12
zero_user_segments() is used from __block_write_begin_int(), for example like the following zero_user_segments(page, 4096, 1024, 512, 918) But new the zero_user_segments() implementation for for HIGHMEM + TRANSPARENT_HUGEPAGE doesn't handle "start > end" case correctly, and hits BUG_ON(). (we can fix __block_write_begin_int() instead though, it is the old and multiple usage) Also it calls kmap_atomic() unnecessarily while start == end == 0. Link: https://lkml.kernel.org/r/87v9ab60r4.fsf@mail.parknet.co.jp Fixes: 0060ef3b4e6d ("mm: support THPs in zero_user_segments") Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Matthew Wilcox <willy@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13hugetlb: do early cow when page pinned on src mmPeter Xu1-4/+62
This is the last missing piece of the COW-during-fork effort when there're pinned pages found. One can reference 70e806e4e645 ("mm: Do early cow for pinned pages during fork() for ptes", 2020-09-27) for more information, since we do similar things here rather than pte this time, but just for hugetlb. Note that after Jason's recent work on 57efa1fe5957 ("mm/gup: prevent gup_fast from racing with COW during fork", 2020-12-15) which is safer and easier to understand, we're safe now within the whole copy_page_range() against gup-fast, we don't need the wr-protect trick that proposed in 70e806e4e645 anymore. Link: https://lkml.kernel.org/r/20210217233547.93892-6-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@ziepe.ca> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Gal Pressman <galpress@amazon.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Kirill Shutemov <kirill@shutemov.name> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Roland Scheidegger <sroland@vmware.com> Cc: VMware Graphics <linux-graphics-maintainer@vmware.com> Cc: Wei Zhang <wzam@amazon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm: use is_cow_mapping() across tree where properPeter Xu4-9/+3
After is_cow_mapping() is exported in mm.h, replace some manual checks elsewhere throughout the tree but start to use the new helper. Link: https://lkml.kernel.org/r/20210217233547.93892-5-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@ziepe.ca> Cc: VMware Graphics <linux-graphics-maintainer@vmware.com> Cc: Roland Scheidegger <sroland@vmware.com> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Gal Pressman <galpress@amazon.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Kirill Shutemov <kirill@shutemov.name> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Wei Zhang <wzam@amazon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm: introduce page_needs_cow_for_dma() for deciding whether cowPeter Xu4-18/+24
We've got quite a few places (pte, pmd, pud) that explicitly checked against whether we should break the cow right now during fork(). It's easier to provide a helper, especially before we work the same thing on hugetlbfs. Since we'll reference is_cow_mapping() in mm.h, move it there too. Actually it suites mm.h more since internal.h is mm/ only, but mm.h is exported to the whole kernel. With that we should expect another patch to use is_cow_mapping() whenever we can across the kernel since we do use it quite a lot but it's always done with raw code against VM_* flags. Link: https://lkml.kernel.org/r/20210217233547.93892-4-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@ziepe.ca> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Gal Pressman <galpress@amazon.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Kirill Shutemov <kirill@shutemov.name> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Roland Scheidegger <sroland@vmware.com> Cc: VMware Graphics <linux-graphics-maintainer@vmware.com> Cc: Wei Zhang <wzam@amazon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13hugetlb: break earlier in add_reservation_in_range() when we canPeter Xu1-1/+1
All the regions maintained in hugetlb reserved map is inclusive on "from" but exclusive on "to". We can break earlier even if rg->from==t because it already means no possible intersection. This does not need a Fixes in all cases because when it happens (rg->from==t) we'll not break out of the loop while we should, however the next thing we'd do is still add the last file_region we'd need and quit the loop in the next round. So this change is not a bugfix (since the old code should still run okay iiuc), but we'd better still touch it up to make it logically sane. Link: https://lkml.kernel.org/r/20210217233547.93892-3-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Gal Pressman <galpress@amazon.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kirill Shutemov <kirill@shutemov.name> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Roland Scheidegger <sroland@vmware.com> Cc: VMware Graphics <linux-graphics-maintainer@vmware.com> Cc: Wei Zhang <wzam@amazon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13hugetlb: dedup the code to add a new file_regionPeter Xu1-24/+27
Patch series "mm/hugetlb: Early cow on fork, and a few cleanups", v5. As reported by Gal [1], we still miss the code clip to handle early cow for hugetlb case, which is true. Again, it still feels odd to fork() after using a few huge pages, especially if they're privately mapped to me.. However I do agree with Gal and Jason in that we should still have that since that'll complete the early cow on fork effort at least, and it'll still fix issues where buffers are not well under control and not easy to apply MADV_DONTFORK. The first two patches (1-2) are some cleanups I noticed when reading into the hugetlb reserve map code. I think it's good to have but they're not necessary for fixing the fork issue. The last two patches (3-4) are the real fix. I tested this with a fork() after some vfio-pci assignment, so I'm pretty sure the page copy path could trigger well (page will be accounted right after the fork()), but I didn't do data check since the card I assigned is some random nic. https://github.com/xzpeter/linux/tree/fork-cow-pin-huge [1] https://lore.kernel.org/lkml/27564187-4a08-f187-5a84-3df50009f6ca@amazon.com/ Introduce hugetlb_resv_map_add() helper to add a new file_region rather than duplication the similar code twice in add_reservation_in_range(). Link: https://lkml.kernel.org/r/20210217233547.93892-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20210217233547.93892-2-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Gal Pressman <galpress@amazon.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Wei Zhang <wzam@amazon.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jann Horn <jannh@google.com> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Kirill Shutemov <kirill@shutemov.name> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: Roland Scheidegger <sroland@vmware.com> Cc: VMware Graphics <linux-graphics-maintainer@vmware.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm/fork: clear PASID for new mmFenghua Yu2-0/+9
When a new mm is created, its PASID should be cleared, i.e. the PASID is initialized to its init state 0 on both ARM and X86. This patch was part of the series introducing mm->pasid, but got lost along the way [1]. It still makes sense to have it, because each address space has a different PASID. And the IOMMU code in iommu_sva_alloc_pasid() expects the pasid field of a new mm struct to be cleared. [1] https://lore.kernel.org/linux-iommu/YDgh53AcQHT+T3L0@otcwcpicx3.sc.intel.com/ Link: https://lkml.kernel.org/r/20210302103837.2562625-1-jean-philippe@linaro.org Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: Jacob Pan <jacob.jun.pan@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm/page_alloc.c: refactor initialization of struct page for holes in memory ↵Mike Rapoport1-83/+75
layout There could be struct pages that are not backed by actual physical memory. This can happen when the actual memory bank is not a multiple of SECTION_SIZE or when an architecture does not register memory holes reserved by the firmware as memblock.memory. Such pages are currently initialized using init_unavailable_mem() function that iterates through PFNs in holes in memblock.memory and if there is a struct page corresponding to a PFN, the fields of this page are set to default values and it is marked as Reserved. init_unavailable_mem() does not take into account zone and node the page belongs to and sets both zone and node links in struct page to zero. Before commit 73a6e474cb37 ("mm: memmap_init: iterate over memblock regions rather that check each PFN") the holes inside a zone were re-initialized during memmap_init() and got their zone/node links right. However, after that commit nothing updates the struct pages representing such holes. On a system that has firmware reserved holes in a zone above ZONE_DMA, for instance in a configuration below: # grep -A1 E820 /proc/iomem 7a17b000-7a216fff : Unknown E820 type 7a217000-7bffffff : System RAM unset zone link in struct page will trigger VM_BUG_ON_PAGE(!zone_spans_pfn(page_zone(page), pfn), page); in set_pfnblock_flags_mask() when called with a struct page from a range other than E820_TYPE_RAM because there are pages in the range of ZONE_DMA32 but the unset zone link in struct page makes them appear as a part of ZONE_DMA. Interleave initialization of the unavailable pages with the normal initialization of memory map, so that zone and node information will be properly set on struct pages that are not backed by the actual memory. With this change the pages for holes inside a zone will get proper zone/node links and the pages that are not spanned by any node will get links to the adjacent zone/node. The holes between nodes will be prepended to the zone/node above the hole and the trailing pages in the last section that will be appended to the zone/node below. [akpm@linux-foundation.org: don't initialize static to zero, use %llu for u64] Link: https://lkml.kernel.org/r/20210225224351.7356-2-rppt@kernel.org Fixes: 73a6e474cb37 ("mm: memmap_init: iterate over memblock regions rather that check each PFN") Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Reported-by: Qian Cai <cai@lca.pw> Reported-by: Andrea Arcangeli <aarcange@redhat.com> Reviewed-by: Baoquan He <bhe@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Łukasz Majczak <lma@semihalf.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: "Sarvela, Tomi P" <tomi.p.sarvela@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13init/Kconfig: make COMPILE_TEST depend on HAS_IOMEMMasahiro Yamada1-2/+1
I read the commit log of the following two: - bc083a64b6c0 ("init/Kconfig: make COMPILE_TEST depend on !UML") - 334ef6ed06fa ("init/Kconfig: make COMPILE_TEST depend on !S390") Both are talking about HAS_IOMEM dependency missing in many drivers. So, 'depends on HAS_IOMEM' seems the direct, sensible solution to me. This does not change the behavior of UML. UML still cannot enable COMPILE_TEST because it does not provide HAS_IOMEM. The current dependency for S390 is too strong. Under the condition of CONFIG_PCI=y, S390 provides HAS_IOMEM, hence can enable COMPILE_TEST. I also removed the meaningless 'default n'. Link: https://lkml.kernel.org/r/20210224140809.1067582-1-masahiroy@kernel.org Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Arnd Bergmann <arnd@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KP Singh <kpsingh@google.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Terrell <terrelln@fb.com> Cc: Quentin Perret <qperret@google.com> Cc: Valentin Schneider <valentin.schneider@arm.com> Cc: "Enrico Weigelt, metux IT consult" <lkml@metux.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13stop_machine: mark helpers __always_inlineArnd Bergmann1-5/+6
With clang-13, some functions only get partially inlined, with a specialized version referring to a global variable. This triggers a harmless build-time check for the intel-rng driver: WARNING: modpost: drivers/char/hw_random/intel-rng.o(.text+0xe): Section mismatch in reference from the function stop_machine() to the function .init.text:intel_rng_hw_init() The function stop_machine() references the function __init intel_rng_hw_init(). This is often because stop_machine lacks a __init annotation or the annotation of intel_rng_hw_init is wrong. In this instance, an easy workaround is to force the stop_machine() function to be inline, along with related interfaces that did not show the same behavior at the moment, but theoretically could. The combination of the two patches listed below triggers the behavior in clang-13, but individually these commits are correct. Link: https://lkml.kernel.org/r/20210225130153.1956990-1-arnd@kernel.org Fixes: fe5595c07400 ("stop_machine: Provide stop_machine_cpuslocked()") Fixes: ee527cd3a20c ("Use stop_machine_run in the Intel RNG driver") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13memblock: fix section mismatch warningArnd Bergmann1-2/+2
The inlining logic in clang-13 is rewritten to often not inline some functions that were inlined by all earlier compilers. In case of the memblock interfaces, this exposed a harmless bug of a missing __init annotation: WARNING: modpost: vmlinux.o(.text+0x507c0a): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock The function memblock_bottom_up() references the variable __meminitdata memblock. This is often because memblock_bottom_up lacks a __meminitdata annotation or the annotation of memblock is wrong. Interestingly, these annotations were present originally, but got removed with the explanation that the __init annotation prevents the function from getting inlined. I checked this again and found that while this is the case with clang, gcc (version 7 through 10, did not test others) does inline the functions regardless. As the previous change was apparently intended to help the clang builds, reverting it to help the newer clang versions seems appropriate as well. gcc builds don't seem to care either way. Link: https://lkml.kernel.org/r/20210225133808.2188581-1-arnd@kernel.org Fixes: 5bdba520c1b3 ("mm: memblock: drop __init from memblock functions to make it inline") Reference: 2cfb3665e864 ("include/linux/memblock.h: add __init to memblock_set_bottom_up()") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Faiyaz Mohammed <faiyazm@codeaurora.org> Cc: Baoquan He <bhe@redhat.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Aslan Bakirov <aslan@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13kbuild: fix ld-version.sh to not be affected by localeMasahiro Yamada1-1/+1
ld-version.sh checks the output from $(LD) --version, but it has a problem on some locales. For example, in Italian: $ LC_MESSAGES=it_IT.UTF-8 ld --version | head -n 1 ld di GNU (GNU Binutils for Debian) 2.35.2 This makes ld-version.sh fail because it expects "GNU ld" for the BFD linker case. Add LC_ALL=C to override the user's locale. BTW, setting LC_MESSAGES=C (or LANG=C) is not enough because it is ineffective if LC_ALL is set on the user's environment. Link: https://bugzilla.kernel.org/show_bug.cgi?id=212105 Reported-by: Marco Scardovi Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Recensito-da: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org>
2021-03-12Merge tag 'nfs-for-5.12-2' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds10-61/+76
Pull NFS client bugfixes from Anna Schumaker: "These are mostly fixes for issues discovered at the recent NFS bakeathon: - Fix PNFS_FLEXFILE_LAYOUT kconfig so it is possible to build into the kernel - Correct size calculationn for create reply length - Set memalloc_nofs_save() for sync tasks to prevent deadlocks - Don't revalidate directory permissions on lookup failure - Don't clear inode cache when lookup fails - Change functions to use nfs_set_cache_invalid() for proper delegation handling - Fix return value of _nfs4_get_security_label() - Return an error when attempting to remove system.nfs4_acl" * tag 'nfs-for-5.12-2' of git://git.linux-nfs.org/projects/anna/linux-nfs: nfs: we don't support removing system.nfs4_acl NFSv4.2: fix return value of _nfs4_get_security_label() NFS: Fix open coded versions of nfs_set_cache_invalid() in NFSv4 NFS: Fix open coded versions of nfs_set_cache_invalid() NFS: Clean up function nfs_mark_dir_for_revalidate() NFS: Don't gratuitously clear the inode cache when lookup failed NFS: Don't revalidate the directory permissions on a lookup failure SUNRPC: Set memalloc_nofs_save() for sync tasks NFS: Correct size calculation for create reply length nfs: fix PNFS_FLEXFILE_LAYOUT Kconfig default
2021-03-12Merge branch 'for-v5.12-rc3' of ↵Linus Torvalds1-11/+1
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull userns fix from Eric Biederman: "Removing the ambiguity broke userspace so this reverts the change" * 'for-v5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: Revert 95ebabde382c ("capabilities: Don't allow writing ambiguous v3 file capabilities")
2021-03-12Merge tag 'scsi-fixes' of ↵Linus Torvalds6-59/+60
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI fixes from James Bottomley: "Ten updates: one non code maintainer update for vmw_pvscsi, five code updates for ibmvfc and four for UFS. All are either trivial patches or bug fixes" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: scsi: vmw_pvscsi: MAINTAINERS: Update maintainer scsi: ufs: Convert sysfs sprintf/snprintf family to sysfs_emit scsi: ufs: Remove redundant checks of !hba in suspend/resume callbacks scsi: ufs: ufs-qcom: Disable interrupt in reset path scsi: ufs: Minor adjustments to error handling scsi: ibmvfc: Reinitialize sub-CRQs and perform channel enquiry after LPM scsi: ibmvfc: Store return code of H_FREE_SUB_CRQ during cleanup scsi: ibmvfc: Treat H_CLOSED as success during sub-CRQ registration scsi: ibmvfc: Fix invalid sub-CRQ handles after hard reset scsi: ibmvfc: Simplify handling of sub-CRQ initialization
2021-03-12Revert 95ebabde382c ("capabilities: Don't allow writing ambiguous v3 file ↵Eric W. Biederman1-11/+1
capabilities") It turns out that there are in fact userspace implementations that care and this recent change caused a regression. https://github.com/containers/buildah/issues/3071 As the motivation for the original change was future development, and the impact is existing real world code just revert this change and allow the ambiguity in v3 file caps. Cc: stable@vger.kernel.org Fixes: 95ebabde382c ("capabilities: Don't allow writing ambiguous v3 file capabilities") Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2021-03-12Merge tag 'block-5.12-2021-03-12-v2' of git://git.kernel.dk/linux-blockLinus Torvalds42-79/+138
Pull block fixes from Jens Axboe: "Mostly just random fixes all over the map. The only odd-one-out change is finally getting the rename of BIO_MAX_PAGES to BIO_MAX_VECS done. This should've been done with the multipage bvec change, but it's been left. Do it now to avoid hassles around changes piling up for the next merge window. Summary: - NVMe pull request: - one more quirk (Dmitry Monakhov) - fix max_zone_append_sectors initialization (Chaitanya Kulkarni) - nvme-fc reset/create race fix (James Smart) - fix status code on aborts/resets (Hannes Reinecke) - fix the CSS check for ZNS namespaces (Chaitanya Kulkarni) - fix a use after free in a debug printk in nvme-rdma (Lv Yunlong) - Follow-up NVMe error fix for NULL 'id' (Christoph) - Fixup for the bd_size_lock being IRQ safe, now that the offending driver has been dropped (Damien). - rsxx probe failure error return (Jia-Ju) - umem probe failure error return (Wei) - s390/dasd unbind fixes (Stefan) - blk-cgroup stats summing fix (Xunlei) - zone reset handling fix (Damien) - Rename BIO_MAX_PAGES to BIO_MAX_VECS (Christoph) - Suppress uevent trigger for hidden devices (Daniel) - Fix handling of discard on busy device (Jan) - Fix stale cache issue with zone reset (Shin'ichiro)" * tag 'block-5.12-2021-03-12-v2' of git://git.kernel.dk/linux-block: nvme: fix the nsid value to print in nvme_validate_or_alloc_ns block: Discard page cache of zone reset target range block: Suppress uevent for hidden device when removed block: rename BIO_MAX_PAGES to BIO_MAX_VECS nvme-pci: add the DISABLE_WRITE_ZEROES quirk for a Samsung PM1725a nvme-rdma: Fix a use after free in nvmet_rdma_write_data_done nvme-core: check ctrl css before setting up zns nvme-fc: fix racing controller reset and create association nvme-fc: return NVME_SC_HOST_ABORTED_CMD when a command has been aborted nvme-fc: set NVME_REQ_CANCELLED in nvme_fc_terminate_exchange() nvme: add NVME_REQ_CANCELLED flag in nvme_cancel_request() nvme: simplify error logic in nvme_validate_ns() nvme: set max_zone_append_sectors nvme_revalidate_zones block: rsxx: fix error return code of rsxx_pci_probe() block: Fix REQ_OP_ZONE_RESET_ALL handling umem: fix error return code in mm_pci_probe() blk-cgroup: Fix the recursive blkg rwstat s390/dasd: fix hanging IO request during DASD driver unbind s390/dasd: fix hanging DASD driver unbind block: Try to handle busy underlying device on discard
2021-03-12Merge tag 'io_uring-5.12-2021-03-12' of git://git.kernel.dk/linux-blockLinus Torvalds5-397/+470
Pull io_uring fixes from Jens Axboe: "Not quite as small this week as I had hoped, but at least this should be the end of it. All the little known issues have been ironed out - most of it little stuff, but cancelations being the bigger part. Only minor tweaks and/or regular fixes expected beyond this point. - Fix the creds tracking for async (io-wq and SQPOLL) - Various SQPOLL fixes related to parking, sharing, forking, IOPOLL, completions, and life times. Much simpler now. - Make IO threads unfreezable by default, on account of a bug report that had them spinning on resume. Honestly not quite sure why thawing leaves us with a perpetual signal pending (causing the spin), but for now make them unfreezable like there were in 5.11 and prior. - Move personality_idr to xarray, solving a use-after-free related to removing an entry from the iterator callback. Buffer idr needs the same treatment. - Re-org around and task vs context tracking, enabling the fixing of cancelations, and then cancelation fixes on top. - Various little bits of cleanups and hardening, and removal of now dead parts" * tag 'io_uring-5.12-2021-03-12' of git://git.kernel.dk/linux-block: (34 commits) io_uring: fix OP_ASYNC_CANCEL across tasks io_uring: cancel sqpoll via task_work io_uring: prevent racy sqd->thread checks io_uring: remove useless ->startup completion io_uring: cancel deferred requests in try_cancel io_uring: perform IOPOLL reaping if canceler is thread itself io_uring: force creation of separate context for ATTACH_WQ and non-threads io_uring: remove indirect ctx into sqo injection io_uring: fix invalid ctx->sq_thread_idle kernel: make IO threads unfreezable by default io_uring: always wait for sqd exited when stopping SQPOLL thread io_uring: remove unneeded variable 'ret' io_uring: move all io_kiocb init early in io_init_req() io-wq: fix ref leak for req in case of exit cancelations io_uring: fix complete_post races for linked req io_uring: add io_disarm_next() helper io_uring: fix io_sq_offload_create error handling io-wq: remove unused 'user' member of io_wq io_uring: Convert personality_idr to XArray io_uring: clean R_DISABLED startup mess ...
2021-03-12Merge tag 'devprop-5.12-rc3' of ↵Linus Torvalds2-10/+21
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull device properties framework fixes from Rafael Wysocki: "Prevent software nodes from being registered before their parents and fix a recent mistake causing already registered software nodes to be registered again in some cases (Heikki Krogerus)" * tag 'devprop-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: software node: Fix device_add_software_node() software node: Fix node registration
2021-03-12Merge tag 'pm-5.12-rc3' of ↵Linus Torvalds4-26/+32
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael Wysocki: "These fix an operating performance point (OPP) reference counting issue and three issues in ARM cpufreq drivers. Specifics: - Add a flag to mark OPPs that are not referenced by he OPP core any more to prevent OPPs from being freed prematurely by mistake (Beata Michalska). - Add ARM Vexpress platforms to the cpufreq-dt-platdev blacklist since the actual scaling of them is handled elsewhere (Sudeep Holla). - Fix a function return value check and a possible use-after-free in the qcom-hw cpufreq driver (Shawn Guo, Wei Yongjun)" * tag 'pm-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: opp: Don't drop extra references to OPPs accidentally cpufreq: blacklist Arm Vexpress platforms in cpufreq-dt-platdev cpufreq: qcom-hw: Fix return value check in qcom_cpufreq_hw_cpu_init() cpufreq: qcom-hw: fix dereferencing freed memory 'data'
2021-03-12nvme: fix the nsid value to print in nvme_validate_or_alloc_nsChristoph Hellwig1-1/+1
ns can be NULL at this point, and my move of the check from the original patch by Chaitanya broke this. Fixes: 0ec84df4953b ("nvme-core: check ctrl css before setting up zns") Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-12Merge tag 'sound-5.12-rc3' of ↵Linus Torvalds10-25/+87
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound Pull sound fixes from Takashi Iwai: "No surprise here, only a collection of device-specific fixes for USB-audio and HD-audio at this time" * tag 'sound-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: ALSA: hda/hdmi: Cancel pending works before suspend ALSA: hda: Avoid spurious unsol event handling during S3/S4 ALSA: hda: Flush pending unsolicited events before suspend ALSA: usb-audio: fix use after free in usb_audio_disconnect ALSA: usb-audio: fix NULL ptr dereference in usb_audio_probe ALSA: hda/ca0132: Add Sound BlasterX AE-5 Plus support ALSA: hda: Drop the BATCH workaround for AMD controllers ALSA: hda/conexant: Add quirk for mute LED control on HP ZBook G5 ALSA: usb-audio: Apply the control quirk to Plantronics headsets ALSA: usb-audio: Fix "cannot get freq eq" errors on Dell AE515 sound bar ALSA: hda: ignore invalid NHLT table ALSA: usb-audio: Disable USB autosuspend properly in setup_disable_autosuspend() ALSA: usb: Add Plantronics C320-M USB ctrl msg delay quirk
2021-03-12Merge tag 'mmc-v5.12-rc2' of ↵Linus Torvalds3-11/+25
git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc Pull MMC fixes from Ulf Hansson: "MMC core: - Fix partition switch time for eMMC MMC host: - mmci: Enforce R1B response to fix busy detection for the stm32 variants - cqhci: Fix crash when removing mmc module/card" * tag 'mmc-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: mmc: cqhci: Fix random crash when remove mmc module/card mmc: core: Fix partition switch time for eMMC mmc: mmci: Add MMC_CAP_NEED_RSP_BUSY for the stm32 variants
2021-03-12Merge tag 'regulator-fix-v5.12-rc2' of ↵Linus Torvalds5-8/+19
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator Pull regulator fixes from Mark Brown: "A small collection fo driver specific fixes that have arrived since the merge window" * tag 'regulator-fix-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: regulator: mt6315: Fix off-by-one for .n_voltages regulator: rt4831: Fix return value check in rt4831_regulator_probe() regulator: pca9450: Clear PRESET_EN bit to fix BUCK1/2/3 voltage setting regulator: qcom-rpmh: Use correct buck for S1C regulator regulator: qcom-rpmh: Correct the pmic5_hfsmps515 buck regulator: pca9450: Fix return value when failing to get sd-vsel GPIO regulator: mt6315: Return REGULATOR_MODE_INVALID for invalid mode
2021-03-12Merge tag 'configfs-for-5.12' of git://git.infradead.org/users/hch/configfsLinus Torvalds1-4/+2
Pull configfs fix from Christoph Hellwig: - fix a use-after-free in __configfs_open_file (Daiyue Zhang) * tag 'configfs-for-5.12' of git://git.infradead.org/users/hch/configfs: configfs: fix a use-after-free in __configfs_open_file
2021-03-12Merge tag 'gfs2-v5.12-rc2-fixes' of ↵Linus Torvalds6-19/+22
git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2 Pull gfs2 fixes from Andreas Gruenbacher: "Various gfs2 fixes" * tag 'gfs2-v5.12-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: gfs2: bypass log flush if the journal is not live gfs2: bypass signal_our_withdraw if no journal gfs2: fix use-after-free in trans_drain gfs2: make function gfs2_make_fs_ro() to void type
2021-03-12Merge tag 'arm64-fixes' of ↵Linus Torvalds17-70/+96
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "We've got a smattering of changes all over the place which we've acrued since -rc1. To my knowledge, there aren't any pending issues at the moment, but there's still plenty of time for something else to crop up... Summary: - Fix booting a 52-bit-VA-aware kernel on Qualcomm Amberwing - Fix pfn_valid() not to reject all ZONE_DEVICE memory - Fix memory tagging setup for hotplugged memory regions - Fix KASAN tagging in page_alloc() when DEBUG_VIRTUAL is enabled - Fix accidental truncation of CPU PMU event counters - Fix error code initialisation when failing probe of DMC620 PMU - Fix return value initialisation for sve-ptrace selftest - Drop broken support for CMDLINE_EXTEND" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: perf/arm_dmc620_pmu: Fix error return code in dmc620_pmu_device_probe() arm64: mm: remove unused __cpu_uses_extended_idmap[_level()] arm64: mm: use a 48-bit ID map when possible on 52-bit VA builds arm64: perf: Fix 64-bit event counter read truncation arm64/mm: Fix __enable_mmu() for new TGRAN range values kselftest: arm64: Fix exit code of sve-ptrace arm64: mte: Map hotplugged memory as Normal Tagged arm64: kasan: fix page_alloc tagging with DEBUG_VIRTUAL arm64/mm: Reorganize pfn_valid() arm64/mm: Fix pfn_valid() for ZONE_DEVICE based memory arm64/mm: Drop THP conditionality from FORCE_MAX_ZONEORDER arm64/mm: Drop redundant ARCH_WANT_HUGE_PMD_SHARE arm64: Drop support for CMDLINE_EXTEND arm64: cpufeatures: Fix handling of CONFIG_CMDLINE for idreg overrides
2021-03-12Merge tag 'for-linus-5.12b-rc3-tag' of ↵Linus Torvalds10-81/+169
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: "Two fix series and a single cleanup: - a small cleanup patch to remove unneeded symbol exports - a series to cleanup Xen grant handling (avoiding allocations in some cases, and using common defines for "invalid" values) - a series to address a race issue in Xen event channel handling" * tag 'for-linus-5.12b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: Xen/gntdev: don't needlessly use kvcalloc() Xen/gnttab: introduce common INVALID_GRANT_{HANDLE,REF} Xen/gntdev: don't needlessly allocate k{,un}map_ops[] Xen: drop exports of {set,clear}_foreign_p2m_mapping() xen/events: avoid handling the same event on two cpus at the same time xen/events: don't unmask an event channel when an eoi is pending xen/events: reset affinity of 2-level event when tearing it down
2021-03-12KVM: LAPIC: Advancing the timer expiration on guest initiated writeWanpeng Li1-0/+1
Advancing the timer expiration should only be necessary on guest initiated writes. When we cancel the timer and clear .pending during state restore, clear expired_tscdeadline as well. Reviewed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Message-Id: <1614818118-965-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-12KVM: x86/mmu: Skip !MMU-present SPTEs when removing SP in exclusive modeSean Christopherson1-0/+11
If mmu_lock is held for write, don't bother setting !PRESENT SPTEs to REMOVED_SPTE when recursively zapping SPTEs as part of shadow page removal. The concurrent write protections provided by REMOVED_SPTE are not needed, there are no backing page side effects to record, and MMIO SPTEs can be left as is since they are protected by the memslot generation, not by ensuring that the MMIO SPTE is unreachable (which is racy with respect to lockless walks regardless of zapping behavior). Skipping !PRESENT drastically reduces the number of updates needed to tear down sparsely populated MMUs, e.g. when tearing down a 6gb VM that didn't touch much memory, 6929/7168 (~96.6%) of SPTEs were '0' and could be skipped. Avoiding the write itself is likely close to a wash, but avoiding __handle_changed_spte() is a clear-cut win as that involves saving and restoring all non-volatile GPRs (it's a subtly big function), as well as several conditional branches before bailing out. Cc: Ben Gardon <bgardon@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210310003029.1250571-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-12KVM: kvmclock: Fix vCPUs > 64 can't be online/hotplugedWanpeng Li1-10/+9
# lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 88 On-line CPU(s) list: 0-63 Off-line CPU(s) list: 64-87 # cat /proc/cmdline BOOT_IMAGE=/vmlinuz-5.10.0-rc3-tlinux2-0050+ root=/dev/mapper/cl-root ro rd.lvm.lv=cl/root rhgb quiet console=ttyS0 LANG=en_US .UTF-8 no-kvmclock-vsyscall # echo 1 > /sys/devices/system/cpu/cpu76/online -bash: echo: write error: Cannot allocate memory The per-cpu vsyscall pvclock data pointer assigns either an element of the static array hv_clock_boot (#vCPU <= 64) or dynamically allocated memory hvclock_mem (vCPU > 64), the dynamically memory will not be allocated if kvmclock vsyscall is disabled, this can result in cpu hotpluged fails in kvmclock_setup_percpu() which returns -ENOMEM. It's broken for no-vsyscall and sometimes you end up with vsyscall disabled if the host does something strange. This patch fixes it by allocating this dynamically memory unconditionally even if vsyscall is disabled. Fixes: 6a1cac56f4 ("x86/kvm: Use __bss_decrypted attribute in shared variables") Reported-by: Zelin Deng <zelin.deng@linux.alibaba.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: stable@vger.kernel.org#v4.19-rc5+ Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Message-Id: <1614130683-24137-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-12kvm: x86: annotate RCU pointersMuhammad Usama Anjum1-2/+2
This patch adds the annotation to fix the following sparse errors: arch/x86/kvm//x86.c:8147:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//x86.c:8147:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//x86.c:8147:15: struct kvm_apic_map * arch/x86/kvm//x86.c:10628:16: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//x86.c:10628:16: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//x86.c:10628:16: struct kvm_apic_map * arch/x86/kvm//x86.c:10629:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//x86.c:10629:15: struct kvm_pmu_event_filter [noderef] __rcu * arch/x86/kvm//x86.c:10629:15: struct kvm_pmu_event_filter * arch/x86/kvm//lapic.c:267:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:267:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:267:15: struct kvm_apic_map * arch/x86/kvm//lapic.c:269:9: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:269:9: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:269:9: struct kvm_apic_map * arch/x86/kvm//lapic.c:637:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:637:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:637:15: struct kvm_apic_map * arch/x86/kvm//lapic.c:994:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:994:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:994:15: struct kvm_apic_map * arch/x86/kvm//lapic.c:1036:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:1036:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:1036:15: struct kvm_apic_map * arch/x86/kvm//lapic.c:1173:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:1173:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:1173:15: struct kvm_apic_map * arch/x86/kvm//pmu.c:190:18: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//pmu.c:190:18: struct kvm_pmu_event_filter [noderef] __rcu * arch/x86/kvm//pmu.c:190:18: struct kvm_pmu_event_filter * arch/x86/kvm//pmu.c:251:18: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//pmu.c:251:18: struct kvm_pmu_event_filter [noderef] __rcu * arch/x86/kvm//pmu.c:251:18: struct kvm_pmu_event_filter * arch/x86/kvm//pmu.c:522:18: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//pmu.c:522:18: struct kvm_pmu_event_filter [noderef] __rcu * arch/x86/kvm//pmu.c:522:18: struct kvm_pmu_event_filter * arch/x86/kvm//pmu.c:522:18: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//pmu.c:522:18: struct kvm_pmu_event_filter [noderef] __rcu * arch/x86/kvm//pmu.c:522:18: struct kvm_pmu_event_filter * Signed-off-by: Muhammad Usama Anjum <musamaanjum@gmail.com> Message-Id: <20210305191123.GA497469@LEGION> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-12Merge branch 'pm-opp'Rafael J. Wysocki2-23/+27
* pm-opp: opp: Don't drop extra references to OPPs accidentally
2021-03-12Merge branch 'opp/linux-next' of ↵Rafael J. Wysocki2-23/+27
git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm Pull an operating performance points (OPP) framework fix for 5.12 from Viresh Kumar: "Fix OPP refcount issue noticed by Beata." * 'opp/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: opp: Don't drop extra references to OPPs accidentally
2021-03-12io_uring: fix OP_ASYNC_CANCEL across tasksPavel Begunkov1-1/+40
IORING_OP_ASYNC_CANCEL tries io-wq cancellation only for current task. If it fails go over tctx_list and try it out for every single tctx. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-12io_uring: cancel sqpoll via task_workPavel Begunkov1-80/+71
1) The first problem is io_uring_cancel_sqpoll() -> io_uring_cancel_task_requests() basically doing park(); park(); and so hanging. 2) Another one is more subtle, when the master task is doing cancellations, but SQPOLL task submits in-between the end of the cancellation but before finish() requests taking a ref to the ctx, and so eternally locking it up. 3) Yet another is a dying SQPOLL task doing io_uring_cancel_sqpoll() and same io_uring_cancel_sqpoll() from the owner task, they race for tctx->wait events. And there probably more of them. Instead do SQPOLL cancellations from within SQPOLL task context via task_work, see io_sqpoll_cancel_sync(). With that we don't need temporal park()/unpark() during cancellation, which is ugly, subtle and anyway doesn't allow to do io_run_task_work() properly. io_uring_cancel_sqpoll() is called only from SQPOLL task context and under sqd locking, so all parking is removed from there. And so, io_sq_thread_[un]park() and io_sq_thread_stop() are not used now by SQPOLL task, and that spare us from some headache. Also remove ctx->sqd_list early to avoid 2). And kill tctx->sqpoll, which is not used anymore. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-12io_uring: prevent racy sqd->thread checksPavel Begunkov1-6/+22
SQPOLL thread to which we're trying to attach may be going away, it's not nice but a more serious problem is if io_sq_offload_create() sees sqd->thread==NULL, and tries to init it with a new thread. There are tons of ways it can be exploited or fail. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>