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2019-11-12lib/scatterlist: Introduce sgl_alloc() and sgl_free()Bart Van Assche2-0/+109
commit e80a0af4759a164214f02da157a3800753ce135f upstream. Many kernel drivers contain code that allocates and frees both a scatterlist and the pages that populate that scatterlist. Introduce functions in lib/scatterlist.c that perform these tasks instead of duplicating this functionality in multiple drivers. Only include these functions in the build if CONFIG_SGL_ALLOC=y to avoid that the kernel size increases if this functionality is not used. Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12dump_stack: avoid the livelock of the dump_lockKevin Hao1-1/+6
commit 5cbf2fff3bba8d3c6a4d47c1754de1cf57e2b01f upstream. In the current code, we use the atomic_cmpxchg() to serialize the output of the dump_stack(), but this implementation suffers the thundering herd problem. We have observed such kind of livelock on a Marvell cn96xx board(24 cpus) when heavily using the dump_stack() in a kprobe handler. Actually we can let the competitors to wait for the releasing of the lock before jumping to atomic_cmpxchg(). This will definitely mitigate the thundering herd problem. Thanks Linus for the suggestion. [akpm@linux-foundation.org: fix comment] Link: http://lkml.kernel.org/r/20191030031637.6025-1-haokexin@gmail.com Fixes: b58d977432c8 ("dump_stack: serialize the output from dump_stack()") Signed-off-by: Kevin Hao <haokexin@gmail.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-07kmemleak: increase DEBUG_KMEMLEAK_EARLY_LOG_SIZE default to 16KNicolas Boichat1-1/+1
[ Upstream commit b751c52bb587ae66f773b15204ef7a147467f4c7 ] The current default value (400) is too low on many systems (e.g. some ARM64 platform takes up 1000+ entries). syzbot uses 16000 as default value, and has proved to be enough on beefy configurations, so let's pick that value. This consumes more RAM on boot (each entry is 160 bytes, so in total ~2.5MB of RAM), but the memory would later be freed (early_log is __initdata). Link: http://lkml.kernel.org/r/20190730154027.101525-1-drinkcat@chromium.org Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> Suggested-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Dmitry Vyukov <dvyukov@google.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Kees Cook <keescook@chromium.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Uladzislau Rezki <urezki@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-16test_firmware: fix a memory leak bugWenwen Wang1-1/+4
[ Upstream commit d4fddac5a51c378c5d3e68658816c37132611e1f ] In test_firmware_init(), the buffer pointed to by the global pointer 'test_fw_config' is allocated through kzalloc(). Then, the buffer is initialized in __test_firmware_config_init(). In the case that the initialization fails, the following execution in test_firmware_init() needs to be terminated with an error code returned to indicate this failure. However, the allocated buffer is not freed on this execution path, leading to a memory leak bug. To fix the above issue, free the allocated buffer before returning from test_firmware_init(). Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu> Link: https://lore.kernel.org/r/1563084696-6865-1-git-send-email-wang6495@umn.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31lib/strscpy: Shut up KASAN false-positives in strscpy()Andrey Ryabinin1-1/+1
[ Upstream commit 1a3241ff10d038ecd096d03380327f2a0b5840a6 ] strscpy() performs the word-at-a-time optimistic reads. So it may may access the memory past the end of the object, which is perfectly fine since strscpy() doesn't use that (past-the-end) data and makes sure the optimistic read won't cross a page boundary. Use new read_word_at_a_time() to shut up the KASAN. Note that this potentially could hide some bugs. In example bellow, stscpy() will copy more than we should (1-3 extra uninitialized bytes): char dst[8]; char *src; src = kmalloc(5, GFP_KERNEL); memset(src, 0xff, 5); strscpy(dst, src, 8); Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZEChristophe Leroy1-4/+5
commit aeb87246537a83c2aff482f3f34a2e0991e02cbc upstream. All mapping iterator logic is based on the assumption that sg->offset is always lower than PAGE_SIZE. But there are situations where sg->offset is such that the SG item is on the second page. In that case sg_copy_to_buffer() fails properly copying the data into the buffer. One of the reason is that the data will be outside the kmapped area used to access that data. This patch fixes the issue by adjusting the mapping iterator offset and pgoffset fields such that offset is always lower than PAGE_SIZE. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Fixes: 4225fc8555a9 ("lib/scatterlist: use page iterator in the mapping iterator") Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-31rslib: Fix handling of of caller provided syndromeFerdinand Blomqvist1-2/+12
[ Upstream commit ef4d6a8556b637ad27c8c2a2cff1dda3da38e9a9 ] Check if the syndrome provided by the caller is zero, and act accordingly. Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190620141039.9874-6-ferdinand.blomqvist@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31rslib: Fix decoding of shortened codesFerdinand Blomqvist1-2/+2
[ Upstream commit 2034a42d1747fc1e1eeef2c6f1789c4d0762cb9c ] The decoding of shortenend codes is broken. It only works as expected if there are no erasures. When decoding with erasures, Lambda (the error and erasure locator polynomial) is initialized from the given erasure positions. The pad parameter is not accounted for by the initialisation code, and hence Lambda is initialized from incorrect erasure positions. The fix is to adjust the erasure positions by the supplied pad. Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190620141039.9874-3-ferdinand.blomqvist@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-10lib/mpi: Fix karactx leak in mpi_powmHerbert Xu1-4/+2
commit c8ea9fce2baf7b643384f36f29e4194fa40d33a6 upstream. Sometimes mpi_powm will leak karactx because a memory allocation failure causes a bail-out that skips the freeing of karactx. This patch moves the freeing of karactx to the end of the function like everything else so that it can't be skipped. Reported-by: syzbot+f7baccc38dcc1e094e77@syzkaller.appspotmail.com Fixes: cdec9cb5167a ("crypto: GnuPG based MPI lib - source files...") Cc: <stable@vger.kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Reviewed-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11test_firmware: Use correct snprintf() limitDan Carpenter1-7/+7
commit bd17cc5a20ae9aaa3ed775f360b75ff93cd66a1d upstream. The limit here is supposed to be how much of the page is left, but it's just using PAGE_SIZE as the limit. The other thing to remember is that snprintf() returns the number of bytes which would have been copied if we had had enough room. So that means that if we run out of space then this code would end up passing a negative value as the limit and the kernel would print an error message. I have change the code to use scnprintf() which returns the number of bytes that were successfully printed (not counting the NUL terminator). Fixes: c92316bf8e94 ("test_firmware: add batched firmware tests") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31kobject: Don't trigger kobject_uevent(KOBJ_REMOVE) twice.Tetsuo Handa1-4/+7
[ Upstream commit c03a0fd0b609e2f5c669c2b7f27c8e1928e9196e ] syzbot is hitting use-after-free bug in uinput module [1]. This is because kobject_uevent(KOBJ_REMOVE) is called again due to commit 0f4dafc0563c6c49 ("Kobject: auto-cleanup on final unref") after memory allocation fault injection made kobject_uevent(KOBJ_REMOVE) from device_del() from input_unregister_device() fail, while uinput_destroy_device() is expecting that kobject_uevent(KOBJ_REMOVE) is not called after device_del() from input_unregister_device() completed. That commit intended to catch cases where nobody even attempted to send "remove" uevents. But there is no guarantee that an event will ultimately be sent. We are at the point of no return as far as the rest of the kernel is concerned; there are no repeats or do-overs. Also, it is not clear whether some subsystem depends on that commit. If no subsystem depends on that commit, it will be better to remove the state_{add,remove}_uevent_sent logic. But we don't want to risk a regression (in a patch which will be backported) by trying to remove that logic. Therefore, as a first step, let's avoid the use-after-free bug by making sure that kobject_uevent(KOBJ_REMOVE) won't be triggered twice. [1] https://syzkaller.appspot.com/bug?id=8b17c134fe938bbddd75a45afaa9e68af43a362d Reported-by: syzbot <syzbot+f648cfb7e0b52bf7ae32@syzkaller.appspotmail.com> Analyzed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Fixes: 0f4dafc0563c6c49 ("Kobject: auto-cleanup on final unref") Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31mm/uaccess: Use 'unsigned long' to placate UBSAN warnings on older GCC versionsPeter Zijlstra2-4/+5
[ Upstream commit 29da93fea3ea39ab9b12270cc6be1b70ef201c9e ] Randy reported objtool triggered on his (GCC-7.4) build: lib/strncpy_from_user.o: warning: objtool: strncpy_from_user()+0x315: call to __ubsan_handle_add_overflow() with UACCESS enabled lib/strnlen_user.o: warning: objtool: strnlen_user()+0x337: call to __ubsan_handle_sub_overflow() with UACCESS enabled This is due to UBSAN generating signed-overflow-UB warnings where it should not. Prior to GCC-8 UBSAN ignored -fwrapv (which the kernel uses through -fno-strict-overflow). Make the functions use 'unsigned long' throughout. Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: luto@kernel.org Link: http://lkml.kernel.org/r/20190424072208.754094071@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31sbitmap: fix improper use of smp_mb__before_atomic()Andrea Parri1-1/+1
commit a0934fd2b1208458e55fc4b48f55889809fce666 upstream. This barrier only applies to the read-modify-write operations; in particular, it does not apply to the atomic_set() primitive. Replace the barrier with an smp_mb(). Fixes: 6c0ca7ae292ad ("sbitmap: fix wakeup hang after sbq resize") Cc: stable@vger.kernel.org Reported-by: "Paul E. McKenney" <paulmck@linux.ibm.com> Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Omar Sandoval <osandov@fb.com> Cc: Ming Lei <ming.lei@redhat.com> Cc: linux-block@vger.kernel.org Cc: "Paul E. McKenney" <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25x86/mm/mem_encrypt: Disable all instrumentation for early SME setupGary Hook1-0/+11
[ Upstream commit b51ce3744f115850166f3d6c292b9c8cb849ad4f ] Enablement of AMD's Secure Memory Encryption feature is determined very early after start_kernel() is entered. Part of this procedure involves scanning the command line for the parameter 'mem_encrypt'. To determine intended state, the function sme_enable() uses library functions cmdline_find_option() and strncmp(). Their use occurs early enough such that it cannot be assumed that any instrumentation subsystem is initialized. For example, making calls to a KASAN-instrumented function before KASAN is set up will result in the use of uninitialized memory and a boot failure. When AMD's SME support is enabled, conditionally disable instrumentation of these dependent functions in lib/string.c and arch/x86/lib/cmdline.c. [ bp: Get rid of intermediary nostackp var and cleanup whitespace. ] Fixes: aca20d546214 ("x86/mm: Add support to make use of Secure Memory Encryption") Reported-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Gary R Hook <gary.hook@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Boris Brezillon <bbrezillon@kernel.org> Cc: Coly Li <colyli@suse.de> Cc: "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: "luto@kernel.org" <luto@kernel.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: "mingo@redhat.com" <mingo@redhat.com> Cc: "peterz@infradead.org" <peterz@infradead.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/155657657552.7116.18363762932464011367.stgit@sosrh3.amd.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-21iov_iter: optimize page_copy_sane()Eric Dumazet1-2/+15
commit 6daef95b8c914866a46247232a048447fff97279 upstream. Avoid cache line miss dereferencing struct page if we can. page_copy_sane() mostly deals with order-0 pages. Extra cache line miss is visible on TCP recvmsg() calls dealing with GRO packets (typically 45 page frags are attached to one skb). Bringing the 45 struct pages into cpu cache while copying the data is not free, since the freeing of the skb (and associated page frags put_page()) can happen after cache lines have been evicted. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-10ubsan: Fix nasty -Wbuiltin-declaration-mismatch GCC-9 warningsAndrey Ryabinin1-26/+23
commit f0996bc2978e02d2ea898101462b960f6119b18f upstream. Building lib/ubsan.c with gcc-9 results in a ton of nasty warnings like this one: lib/ubsan.c warning: conflicting types for built-in function ‘__ubsan_handle_negate_overflow’; expected ‘void(void *, void *)’ [-Wbuiltin-declaration-mismatch] The kernel's declarations of __ubsan_handle_*() often uses 'unsigned long' types in parameters while GCC these parameters as 'void *' types, hence the mismatch. Fix this by using 'void *' to match GCC's declarations. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Fixes: c6d308534aef ("UBSAN: run-time undefined behavior sanity checker") Cc: <stable@vger.kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-08kasan: prevent compiler from optimizing away memset in testsAndrey Konovalov1-0/+1
commit 69ca372c100fba99c78ef826a1795aa86e4f01a8 upstream. A compiler can optimize away memset calls by replacing them with mov instructions. There are KASAN tests that specifically test that KASAN correctly handles memset calls so we don't want this optimization to happen. The solution is to add -fno-builtin flag to test_kasan.ko Link: http://lkml.kernel.org/r/105ec9a308b2abedb1a0d1fdced0c22d765e4732.1519924383.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Nick Terrell <terrelln@fb.com> Cc: Chris Mason <clm@fb.com> Cc: Yury Norov <ynorov@caviumnetworks.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "Luis R . Rodriguez" <mcgrof@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com> Cc: Jeff Layton <jlayton@redhat.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Cc: Kostya Serebryany <kcc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-08kasan: remove redundant initialization of variable 'real_size'Colin Ian King1-1/+1
commit 48c232395431c23d35cf3b4c5a090bd793316578 upstream. Variable real_size is initialized with a value that is never read, it is re-assigned a new value later on, hence the initialization is redundant and can be removed. Cleans up clang warning: lib/test_kasan.c:422:21: warning: Value stored to 'real_size' during its initialization is never read Link: http://lkml.kernel.org/r/20180206144950.32457-1-colin.king@canonical.com Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-02lib/Kconfig.debug: fix build error without CONFIG_BLOCKYueHaibing1-0/+1
commit ae3d6a323347940f0548bbb4b17f0bb2e9164169 upstream. If CONFIG_TEST_KMOD is set to M, while CONFIG_BLOCK is not set, XFS and BTRFS can not be compiled successly. Link: http://lkml.kernel.org/r/20190410075434.35220-1-yuehaibing@huawei.com Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Reported-by: Hulk Robot <hulkci@huawei.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-20lib/div64.c: off by one in shiftStanislaw Gruszka1-2/+2
[ Upstream commit cdc94a37493135e355dfc0b0e086d84e3eadb50d ] fls counts bits starting from 1 to 32 (returns 0 for zero argument). If we add 1 we shift right one bit more and loose precision from divisor, what cause function incorect results with some numbers. Corrected code was tested in user-space, see bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202391 Link: http://lkml.kernel.org/r/1548686944-11891-1-git-send-email-sgruszka@redhat.com Fixes: 658716d19f8f ("div64_u64(): improve precision on 32bit platforms") Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Reported-by: Siarhei Volkau <lis8215@gmail.com> Tested-by: Siarhei Volkau <lis8215@gmail.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-17lib/string.c: implement a basic bcmpNick Desaulniers1-0/+20
[ Upstream commit 5f074f3e192f10c9fade898b9b3b8812e3d83342 ] A recent optimization in Clang (r355672) lowers comparisons of the return value of memcmp against zero to comparisons of the return value of bcmp against zero. This helps some platforms that implement bcmp more efficiently than memcmp. glibc simply aliases bcmp to memcmp, but an optimized implementation is in the works. This results in linkage failures for all targets with Clang due to the undefined symbol. For now, just implement bcmp as a tailcail to memcmp to unbreak the build. This routine can be further optimized in the future. Other ideas discussed: * A weak alias was discussed, but breaks for architectures that define their own implementations of memcmp since aliases to declarations are not permitted (only definitions). Arch-specific memcmp implementations typically declare memcmp in C headers, but implement them in assembly. * -ffreestanding also is used sporadically throughout the kernel. * -fno-builtin-bcmp doesn't work when doing LTO. Link: https://bugs.llvm.org/show_bug.cgi?id=41035 Link: https://code.woboq.org/userspace/glibc/string/memcmp.c.html#bcmp Link: https://github.com/llvm/llvm-project/commit/8e16d73346f8091461319a7dfc4ddd18eedcff13 Link: https://github.com/ClangBuiltLinux/linux/issues/416 Link: http://lkml.kernel.org/r/20190313211335.165605-1-ndesaulniers@google.com Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reported-by: Nathan Chancellor <natechancellor@gmail.com> Reported-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Suggested-by: Arnd Bergmann <arnd@arndb.de> Suggested-by: James Y Knight <jyknight@google.com> Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com> Suggested-by: Nathan Chancellor <natechancellor@gmail.com> Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: David Laight <David.Laight@ACULAB.COM> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05ARM: 8833/1: Ensure that NEON code always compiles with ClangNathan Chancellor1-1/+1
[ Upstream commit de9c0d49d85dc563549972edc5589d195cd5e859 ] While building arm32 allyesconfig, I ran into the following errors: arch/arm/lib/xor-neon.c:17:2: error: You should compile this file with '-mfloat-abi=softfp -mfpu=neon' In file included from lib/raid6/neon1.c:27: /home/nathan/cbl/prebuilt/lib/clang/8.0.0/include/arm_neon.h:28:2: error: "NEON support not enabled" Building V=1 showed NEON_FLAGS getting passed along to Clang but __ARM_NEON__ was not getting defined. Ultimately, it boils down to Clang only defining __ARM_NEON__ when targeting armv7, rather than armv6k, which is the '-march' value for allyesconfig. >From lib/Basic/Targets/ARM.cpp in the Clang source: // This only gets set when Neon instructions are actually available, unlike // the VFP define, hence the soft float and arch check. This is subtly // different from gcc, we follow the intent which was that it should be set // when Neon instructions are actually available. if ((FPU & NeonFPU) && !SoftFloat && ArchVersion >= 7) { Builder.defineMacro("__ARM_NEON", "1"); Builder.defineMacro("__ARM_NEON__"); // current AArch32 NEON implementations do not support double-precision // floating-point even when it is present in VFP. Builder.defineMacro("__ARM_NEON_FP", "0x" + Twine::utohexstr(HW_FP & ~HW_FP_DP)); } Ard Biesheuvel recommended explicitly adding '-march=armv7-a' at the beginning of the NEON_FLAGS definitions so that __ARM_NEON__ always gets definined by Clang. This doesn't functionally change anything because that code will only run where NEON is supported, which is implicitly armv7. Link: https://github.com/ClangBuiltLinux/linux/issues/287 Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Nicolas Pitre <nico@linaro.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05kprobes: Prohibit probing on bsearch()Andrea Righi1-0/+2
[ Upstream commit 02106f883cd745523f7766d90a739f983f19e650 ] Since kprobe breakpoing handler is using bsearch(), probing on this routine can cause recursive breakpoint problem. int3 ->do_int3() ->ftrace_int3_handler() ->ftrace_location() ->ftrace_location_range() ->bsearch() -> int3 Prohibit probing on bsearch(). Signed-off-by: Andrea Righi <righi.andrea@gmail.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/154998813406.31052.8791425358974650922.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05lib/int_sqrt: optimize initial value computePeter Zijlstra1-4/+2
commit f8ae107eef209bff29a5816bc1aad40d5cd69a80 upstream. The initial value (@m) compute is: m = 1UL << (BITS_PER_LONG - 2); while (m > x) m >>= 2; Which is a linear search for the highest even bit smaller or equal to @x We can implement this using a binary search using __fls() (or better when its hardware implemented). m = 1UL << (__fls(x) & ~1UL); Especially for small values of @x; which are the more common arguments when doing a CDF on idle times; the linear search is near to worst case, while the binary search of __fls() is a constant 6 (or 5 on 32bit) branches. cycles: branches: branch-misses: PRE: hot: 43.633557 +- 0.034373 45.333132 +- 0.002277 0.023529 +- 0.000681 cold: 207.438411 +- 0.125840 45.333132 +- 0.002277 6.976486 +- 0.004219 SOFTWARE FLS: hot: 29.576176 +- 0.028850 26.666730 +- 0.004511 0.019463 +- 0.000663 cold: 165.947136 +- 0.188406 26.666746 +- 0.004511 6.133897 +- 0.004386 HARDWARE FLS: hot: 24.720922 +- 0.025161 20.666784 +- 0.004509 0.020836 +- 0.000677 cold: 132.777197 +- 0.127471 20.666776 +- 0.004509 5.080285 +- 0.003874 Averages computed over all values <128k using a LFSR to generate order. Cold numbers have a LFSR based branch trace buffer 'confuser' ran between each int_sqrt() invocation. Link: http://lkml.kernel.org/r/20171020164644.936577234@infradead.org Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Suggested-by: Joe Perches <joe@perches.com> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Anshul Garg <aksgarg1989@gmail.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: David Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Michael Davidson <md@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03rhashtable: Still do rehash when we get EEXISTHerbert Xu1-2/+6
[ Upstream commit 408f13ef358aa5ad56dc6230c2c7deb92cf462b1 ] As it stands if a shrink is delayed because of an outstanding rehash, we will go into a rescheduling loop without ever doing the rehash. This patch fixes this by still carrying out the rehash and then rescheduling so that we can shrink after the completion of the rehash should it still be necessary. The return value of EEXIST captures this case and other cases (e.g., another thread expanded/rehashed the table at the same time) where we should still proceed with the rehash. Fixes: da20420f83ea ("rhashtable: Add nested tables") Reported-by: Josh Elsasser <jelsasser@appneta.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Josh Elsasser <jelsasser@appneta.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27lib/int_sqrt: optimize small argumentPeter Zijlstra1-0/+3
commit 3f3295709edea6268ff1609855f498035286af73 upstream. The current int_sqrt() computation is sub-optimal for the case of small @x. Which is the interesting case when we're going to do cumulative distribution functions on idle times, which we assume to be a random variable, where the target residency of the deepest idle state gives an upper bound on the variable (5e6ns on recent Intel chips). In the case of small @x, the compute loop: while (m != 0) { b = y + m; y >>= 1; if (x >= b) { x -= b; y += m; } m >>= 2; } can be reduced to: while (m > x) m >>= 2; Because y==0, b==m and until x>=m y will remain 0. And while this is computationally equivalent, it runs much faster because there's less code, in particular less branches. cycles: branches: branch-misses: OLD: hot: 45.109444 +- 0.044117 44.333392 +- 0.002254 0.018723 +- 0.000593 cold: 187.737379 +- 0.156678 44.333407 +- 0.002254 6.272844 +- 0.004305 PRE: hot: 67.937492 +- 0.064124 66.999535 +- 0.000488 0.066720 +- 0.001113 cold: 232.004379 +- 0.332811 66.999527 +- 0.000488 6.914634 +- 0.006568 POST: hot: 43.633557 +- 0.034373 45.333132 +- 0.002277 0.023529 +- 0.000681 cold: 207.438411 +- 0.125840 45.333132 +- 0.002277 6.976486 +- 0.004219 Averages computed over all values <128k using a LFSR to generate order. Cold numbers have a LFSR based branch trace buffer 'confuser' ran between each int_sqrt() invocation. Link: http://lkml.kernel.org/r/20171020164644.876503355@infradead.org Fixes: 30493cc9dddb ("lib/int_sqrt.c: optimize square root algorithm") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Suggested-by: Anshul Garg <aksgarg1989@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Joe Perches <joe@perches.com> Cc: David Miller <davem@davemloft.net> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Michael Davidson <md@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23assoc_array: Fix shortcut creationDavid Howells1-3/+5
[ Upstream commit bb2ba2d75a2d673e76ddaf13a9bd30d6a8b1bb08 ] Fix the creation of shortcuts for which the length of the index key value is an exact multiple of the machine word size. The problem is that the code that blanks off the unused bits of the shortcut value malfunctions if the number of bits in the last word equals machine word size. This is due to the "<<" operator being given a shift of zero in this case, and so the mask that should be all zeros is all ones instead. This causes the subsequent masking operation to clear everything rather than clearing nothing. Ordinarily, the presence of the hash at the beginning of the tree index key makes the issue very hard to test for, but in this case, it was encountered due to a development mistake that caused the hash output to be either 0 (keyring) or 1 (non-keyring) only. This made it susceptible to the keyctl/unlink/valid test in the keyutils package. The fix is simply to skip the blanking if the shift would be 0. For example, an index key that is 64 bits long would produce a 0 shift and thus a 'blank' of all 1s. This would then be inverted and AND'd onto the index_key, incorrectly clearing the entire last word. Fixes: 3cb989501c26 ("Add a generic associative array implementation.") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <james.morris@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-14lib/test_kmod.c: potential double free in error handlingDan Carpenter1-1/+1
[ Upstream commit db7ddeab3ce5d64c9696e70d61f45ea9909cd196 ] There is a copy and paste bug so we set "config->test_driver" to NULL twice instead of setting "config->test_fs". Smatch complains that it leads to a double free: lib/test_kmod.c:840 __kmod_config_init() warn: 'config->test_fs' double freed Link: http://lkml.kernel.org/r/20190121140011.GA14283@kadam Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12seq_buf: Make seq_buf_puts() null-terminate the bufferMichael Ellerman1-1/+5
[ Upstream commit 0464ed24380905d640030d368cd84a4e4d1e15e2 ] Currently seq_buf_puts() will happily create a non null-terminated string for you in the buffer. This is particularly dangerous if the buffer is on the stack. For example: char buf[8]; char secret = "secret"; struct seq_buf s; seq_buf_init(&s, buf, sizeof(buf)); seq_buf_puts(&s, "foo"); printk("Message is %s\n", buf); Can result in: Message is fooªªªªªsecret We could require all users to memset() their buffer to zero before use. But that seems likely to be forgotten and lead to bugs. Instead we can change seq_buf_puts() to always leave the buffer in a null-terminated state. The only downside is that this makes the buffer 1 character smaller for seq_buf_puts(), but that seems like a good trade off. Link: http://lkml.kernel.org/r/20181019042109.8064-1-mpe@ellerman.id.au Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-13lib: fix build failure in CONFIG_DEBUG_VIRTUAL testChristophe Leroy1-0/+1
commit 10fdf838e5f540beca466e9d1325999c072e5d3f upstream. On several arches, virt_to_phys() is in io.h Build fails without it: CC lib/test_debug_virtual.o lib/test_debug_virtual.c: In function 'test_debug_virtual_init': lib/test_debug_virtual.c:26:7: error: implicit declaration of function 'virt_to_phys' [-Werror=implicit-function-declaration] pa = virt_to_phys(va); ^ Fixes: e4dace361552 ("lib: add test module for CONFIG_DEBUG_VIRTUAL") CC: stable@vger.kernel.org Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-13raid6/ppc: Fix build for clangJoel Stanley1-0/+15
commit e213574a449f7a57d4202c1869bbc7680b6b5521 upstream. We cannot build these files with clang as it does not allow altivec instructions in assembly when -msoft-float is passed. Jinsong Ji <jji@us.ibm.com> wrote: > We currently disable Altivec/VSX support when enabling soft-float. So > any usage of vector builtins will break. > > Enable Altivec/VSX with soft-float may need quite some clean up work, so > I guess this is currently a limitation. > > Removing -msoft-float will make it work (and we are lucky that no > floating point instructions will be generated as well). This is a workaround until the issue is resolved in clang. Link: https://bugs.llvm.org/show_bug.cgi?id=31177 Link: https://github.com/ClangBuiltLinux/linux/issues/239 Signed-off-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> [nc: Use 'ifeq ($(cc-name),clang)' instead of 'ifdef CONFIG_CC_IS_CLANG' because that config does not exist in 4.14; the Kconfig rewrite that added that config happened in 4.18] Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-17lib/rbtree-test: lower default paramsDavidlohr Bueso2-3/+3
commit 0b548e33e6cb2bff240fdaf1783783be15c29080 upstream. Fengguang reported soft lockups while running the rbtree and interval tree test modules. The logic for these tests all occur in init phase, and we currently are pounding with the default values for number of nodes and number of iterations of each test. Reduce the latter by two orders of magnitude. This does not influence the value of the tests in that one thousand times by default is enough to get the picture. Link: http://lkml.kernel.org/r/20171109161715.xai2dtwqw2frhkcm@linux-n805 Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-17debugobjects: avoid recursive calls with kmemleakQian Cai1-3/+2
[ Upstream commit 8de456cf87ba863e028c4dd01bae44255ce3d835 ] CONFIG_DEBUG_OBJECTS_RCU_HEAD does not play well with kmemleak due to recursive calls. fill_pool kmemleak_ignore make_black_object put_object __call_rcu (kernel/rcu/tree.c) debug_rcu_head_queue debug_object_activate debug_object_init fill_pool kmemleak_ignore make_black_object ... So add SLAB_NOLEAKTRACE to kmem_cache_create() to not register newly allocated debug objects at all. Link: http://lkml.kernel.org/r/20181126165343.2339-1-cai@gmx.us Signed-off-by: Qian Cai <cai@gmx.us> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Waiman Long <longman@redhat.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yang Shi <yang.shi@linux.alibaba.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-13swiotlb: clean up reportingKees Cook1-11/+9
commit 7d63fb3af87aa67aa7d24466e792f9d7c57d8e79 upstream. This removes needless use of '%p', and refactors the printk calls to use pr_*() helpers instead. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de> [bwh: Backported to 4.14: - Adjust filename - Remove "swiotlb: " prefix from an additional log message] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-13test_firmware: fix error return getting clobberedColin Ian King1-0/+1
[ Upstream commit 8bb0a88600f0267cfcc245d34f8c4abe8c282713 ] In the case where eq->fw->size > PAGE_SIZE the error return rc is being set to EINVAL however this is being overwritten to rc = req->fw->size because the error exit path via label 'out' is not being taken. Fix this by adding the jump to the error exit path 'out'. Detected by CoverityScan, CID#1453465 ("Unused value") Fixes: c92316bf8e94 ("test_firmware: add batched firmware tests") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-08kobject: Replace strncpy with memcpyGuenter Roeck1-1/+1
commit 77d2a24b6107bd9b3bf2403a65c1428a9da83dd0 upstream. gcc 8.1.0 complains: lib/kobject.c:128:3: warning: 'strncpy' output truncated before terminating nul copying as many bytes from a string as its length [-Wstringop-truncation] lib/kobject.c: In function 'kobject_get_path': lib/kobject.c:125:13: note: length computed here Using strncpy() is indeed less than perfect since the length of data to be copied has already been determined with strlen(). Replace strncpy() with memcpy() to address the warning and optimize the code a little. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08test_hexdump: use memcpy instead of strncpyLinus Torvalds1-1/+1
commit b1286ed7158e9b62787508066283ab0b8850b518 upstream. New versions of gcc reasonably warn about the odd pattern of strncpy(p, q, strlen(q)); which really doesn't make sense: the strncpy() ends up being just a slow and odd way to write memcpy() in this case. Apparently there was a patch for this floating around earlier, but it got lost. Acked-again-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05lib/test_kmod.c: fix rmmod double freeLuis Chamberlain1-1/+0
commit 5618cf031fecda63847cafd1091e7b8bd626cdb1 upstream. We free the misc device string twice on rmmod; fix this. Without this we cannot remove the module without crashing. Link: http://lkml.kernel.org/r/20181124050500.5257-1-mcgrof@kernel.org Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Reported-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: <stable@vger.kernel.org> [4.12+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-27lib/raid6: Fix arm64 test buildJeremy Linton1-2/+2
[ Upstream commit 313a06e636808387822af24c507cba92703568b1 ] The lib/raid6/test fails to build the neon objects on arm64 because the correct machine type is 'aarch64'. Once this is correctly enabled, the neon recovery objects need to be added to the build. Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-21lib/ubsan.c: don't mark __ubsan_handle_builtin_unreachable as noreturnArnd Bergmann1-2/+1
commit 1c23b4108d716cc848b38532063a8aca4f86add8 upstream. gcc-8 complains about the prototype for this function: lib/ubsan.c:432:1: error: ignoring attribute 'noreturn' in declaration of a built-in function '__ubsan_handle_builtin_unreachable' because it conflicts with attribute 'const' [-Werror=attributes] This is actually a GCC's bug. In GCC internals __ubsan_handle_builtin_unreachable() declared with both 'noreturn' and 'const' attributes instead of only 'noreturn': https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84210 Workaround this by removing the noreturn attribute. [aryabinin: add information about GCC bug in changelog] Link: http://lkml.kernel.org/r/20181107144516.4587-1-aryabinin@virtuozzo.com Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Acked-by: Olof Johansson <olof@lixom.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-13locking/lockdep: Fix debug_locks off performance problemWaiman Long1-1/+1
[ Upstream commit 9506a7425b094d2f1d9c877ed5a78f416669269b ] It was found that when debug_locks was turned off because of a problem found by the lockdep code, the system performance could drop quite significantly when the lock_stat code was also configured into the kernel. For instance, parallel kernel build time on a 4-socket x86-64 server nearly doubled. Further analysis into the cause of the slowdown traced back to the frequent call to debug_locks_off() from the __lock_acquired() function probably due to some inconsistent lockdep states with debug_locks off. The debug_locks_off() function did an unconditional atomic xchg to write a 0 value into debug_locks which had already been set to 0. This led to severe cacheline contention in the cacheline that held debug_locks. As debug_locks is being referenced in quite a few different places in the kernel, this greatly slow down the system performance. To prevent that trashing of debug_locks cacheline, lock_acquired() and lock_contended() now checks the state of debug_locks before proceeding. The debug_locks_off() function is also modified to check debug_locks before calling __debug_locks_off(). Signed-off-by: Waiman Long <longman@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/1539913518-15598-1-git-send-email-longman@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-04test_bpf: Fix testing with CONFIG_BPF_JIT_ALWAYS_ON=y on other archesThadeu Lima de Souza Cascardo1-1/+1
[ Upstream commit 52fda36d63bfc8c8e8ae5eda8eb5ac6f52cd67ed ] Function bpf_fill_maxinsns11 is designed to not be able to be JITed on x86_64. So, it fails when CONFIG_BPF_JIT_ALWAYS_ON=y, and commit 09584b406742 ("bpf: fix selftests/bpf test_kmod.sh failure when CONFIG_BPF_JIT_ALWAYS_ON=y") makes sure that failure is detected on that case. However, it does not fail on other architectures, which have a different JIT compiler design. So, test_bpf has started to fail to load on those. After this fix, test_bpf loads fine on both x86_64 and ppc64el. Fixes: 09584b406742 ("bpf: fix selftests/bpf test_kmod.sh failure when CONFIG_BPF_JIT_ALWAYS_ON=y") Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Reviewed-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-10-04scsi: klist: Make it safe to use klists in atomic contextBart Van Assche1-4/+6
[ Upstream commit 624fa7790f80575a4ec28fbdb2034097dc18d051 ] In the scsi_transport_srp implementation it cannot be avoided to iterate over a klist from atomic context when using the legacy block layer instead of blk-mq. Hence this patch that makes it safe to use klists in atomic context. This patch avoids that lockdep reports the following: WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&(&k->k_lock)->rlock); local_irq_disable(); lock(&(&q->__queue_lock)->rlock); lock(&(&k->k_lock)->rlock); <Interrupt> lock(&(&q->__queue_lock)->rlock); stack backtrace: Workqueue: kblockd blk_timeout_work Call Trace: dump_stack+0xa4/0xf5 check_usage+0x6e6/0x700 __lock_acquire+0x185d/0x1b50 lock_acquire+0xd2/0x260 _raw_spin_lock+0x32/0x50 klist_next+0x47/0x190 device_for_each_child+0x8e/0x100 srp_timed_out+0xaf/0x1d0 [scsi_transport_srp] scsi_times_out+0xd4/0x410 [scsi_mod] blk_rq_timed_out+0x36/0x70 blk_timeout_work+0x1b5/0x220 process_one_work+0x4fe/0xad0 worker_thread+0x63/0x5a0 kthread+0x1c1/0x1e0 ret_from_fork+0x24/0x30 See also commit c9ddf73476ff ("scsi: scsi_transport_srp: Fix shost to rport translation"). Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: James Bottomley <jejb@linux.vnet.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-19rhashtable: add schedule pointsEric Dumazet1-0/+2
Rehashing and destroying large hash table takes a lot of time, and happens in process context. It is safe to add cond_resched() in rhashtable_rehash_table() and rhashtable_free_and_destroy() Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net> (cherry picked from commit ae6da1f503abb5a5081f9f6c4a6881de97830f3e) Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15debugobjects: Make stack check warning more informativeJoel Fernandes (Google)1-2/+5
commit fc91a3c4c27acdca0bc13af6fbb68c35cfd519f2 upstream. While debugging an issue debugobject tracking warned about an annotation issue of an object on stack. It turned out that the issue was due to the object in concern being on a different stack which was due to another issue. Thomas suggested to print the pointers and the location of the stack for the currently running task. This helped to figure out that the object was on the wrong stack. As this is general useful information for debugging similar issues, make the error message more informative by printing the pointers. [ tglx: Massaged changelog ] Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Waiman Long <longman@redhat.com> Acked-by: Yang Shi <yang.shi@linux.alibaba.com> Cc: kernel-team@android.com Cc: Arnd Bergmann <arnd@arndb.de> Cc: astrachan@google.com Link: https://lkml.kernel.org/r/20180723212531.202328-1-joel@joelfernandes.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05printk/nmi: Prevent deadlock when accessing the main log buffer in NMIPetr Mladek1-3/+0
commit 03fc7f9c99c1e7ae2925d459e8487f1a6f199f79 upstream. The commit 719f6a7040f1bdaf96 ("printk: Use the main logbuf in NMI when logbuf_lock is available") brought back the possible deadlocks in printk() and NMI. The check of logbuf_lock is done only in printk_nmi_enter() to prevent mixed output. But another CPU might take the lock later, enter NMI, and: + Both NMIs might be serialized by yet another lock, for example, the one in nmi_cpu_backtrace(). + The other CPU might get stopped in NMI, see smp_send_stop() in panic(). The only safe solution is to use trylock when storing the message into the main log-buffer. It might cause reordering when some lines go to the main lock buffer directly and others are delayed via the per-CPU buffer. It means that it is not useful in general. This patch replaces the problematic NMI deferred context with NMI direct context. It can be used to mark a code that might produce many messages in NMI and the risk of losing them is more critical than problems with eventual reordering. The context is then used when dumping trace buffers on oops. It was the primary motivation for the original fix. Also the reordering is even smaller issue there because some traces have their own time stamps. Finally, nmi_cpu_backtrace() need not longer be serialized because it will always us the per-CPU buffers again. Fixes: 719f6a7040f1bdaf96 ("printk: Use the main logbuf in NMI when logbuf_lock is available") Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180627142028.11259-1-pmladek@suse.com To: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-17ioremap: Update pgtable free interfaces with addrChintan Pandya1-2/+2
commit 785a19f9d1dd8a4ab2d0633be4656653bd3de1fc upstream. The following kernel panic was observed on ARM64 platform due to a stale TLB entry. 1. ioremap with 4K size, a valid pte page table is set. 2. iounmap it, its pte entry is set to 0. 3. ioremap the same address with 2M size, update its pmd entry with a new value. 4. CPU may hit an exception because the old pmd entry is still in TLB, which leads to a kernel panic. Commit b6bdb7517c3d ("mm/vmalloc: add interfaces to free unmapped page table") has addressed this panic by falling to pte mappings in the above case on ARM64. To support pmd mappings in all cases, TLB purge needs to be performed in this case on ARM64. Add a new arg, 'addr', to pud_free_pmd_page() and pmd_free_pte_page() so that TLB purge can be added later in seprate patches. [toshi.kani@hpe.com: merge changes, rewrite patch description] Fixes: 28ee90fe6048 ("x86/mm: implement free pmd/pte page interfaces") Signed-off-by: Chintan Pandya <cpandya@codeaurora.org> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: mhocko@suse.com Cc: akpm@linux-foundation.org Cc: hpa@zytor.com Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: Will Deacon <will.deacon@arm.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: stable@vger.kernel.org Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20180627141348.21777-3-toshi.kani@hpe.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-25lib/rhashtable: consider param->min_size when setting initial table sizeDavidlohr Bueso1-6/+11
[ Upstream commit 107d01f5ba10f4162c38109496607eb197059064 ] rhashtable_init() currently does not take into account the user-passed min_size parameter unless param->nelem_hint is set as well. As such, the default size (number of buckets) will always be HASH_DEFAULT_SIZE even if the smallest allowed size is larger than that. Remediate this by unconditionally calling into rounded_hashtable_size() and handling things accordingly. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03lib/vsprintf: Remove atomic-unsafe support for %pCrGeert Uytterhoeven1-3/+0
commit 666902e42fd8344b923c02dc5b0f37948ff4f225 upstream. "%pCr" formats the current rate of a clock, and calls clk_get_rate(). The latter obtains a mutex, hence it must not be called from atomic context. Remove support for this rarely-used format, as vsprintf() (and e.g. printk()) must be callable from any context. Any remaining out-of-tree users will start seeing the clock's name printed instead of its rate. Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com> Fixes: 900cca2944254edd ("lib/vsprintf: add %pC{,n,r} format specifiers for clocks") Link: http://lkml.kernel.org/r/1527845302-12159-5-git-send-email-geert+renesas@glider.be To: Jia-Ju Bai <baijiaju1990@gmail.com> To: Jonathan Corbet <corbet@lwn.net> To: Michael Turquette <mturquette@baylibre.com> To: Stephen Boyd <sboyd@kernel.org> To: Zhang Rui <rui.zhang@intel.com> To: Eduardo Valentin <edubezval@gmail.com> To: Eric Anholt <eric@anholt.net> To: Stefan Wahren <stefan.wahren@i2se.com> To: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-doc@vger.kernel.org Cc: linux-clk@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: linux-serial@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-renesas-soc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: stable@vger.kernel.org # 4.1+ Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30lib/test_kmod.c: fix limit check on number of test devices createdLuis R. Rodriguez1-1/+1
[ Upstream commit ac68b1b3b9c73e652dc7ce0585672e23c5a2dca4 ] As reported by Dan the parentheses is in the wrong place, and since unlikely() call returns either 0 or 1 it's never less than zero. The second issue is that signed integer overflows like "INT_MAX + 1" are undefined behavior. Since num_test_devs represents the number of devices, we want to stop prior to hitting the max, and not rely on the wrap arround at all. So just cap at num_test_devs + 1, prior to assigning a new device. Link: http://lkml.kernel.org/r/20180224030046.24238-1-mcgrof@kernel.org Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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