kernel/linux.git/lib, branch v4.9.146

debugobjects: avoid recursive calls with kmemleak

2018-12-17T08:38:35+00:00

[ 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 Suggested-by: Catalin Marinas Acked-by: Waiman Long Acked-by: Catalin Marinas Cc: Thomas Gleixner Cc: Yang Shi Cc: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

swiotlb: clean up reporting

2018-12-13T08:20:29+00:00

commit 7d63fb3af87aa67aa7d24466e792f9d7c57d8e79 upstream. This removes needless use of '%p', and refactors the printk calls to use pr_*() helpers instead. Signed-off-by: Kees Cook Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: Christoph Hellwig [bwh: Backported to 4.9: - Adjust filename - Remove "swiotlb: " prefix from an additional log message] Signed-off-by: Ben Hutchings Signed-off-by: Sasha Levin

kobject: Replace strncpy with memcpy

2018-12-08T12:05:05+00:00

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 Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

test_hexdump: use memcpy instead of strncpy

2018-12-08T12:05:04+00:00

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 Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

lib/raid6: Fix arm64 test build

2018-11-27T15:09:39+00:00

[ 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 Signed-off-by: Jeremy Linton Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin

lib/ubsan.c: don't mark __ubsan_handle_builtin_unreachable as noreturn

2018-11-21T08:26:03+00:00

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 Signed-off-by: Andrey Ryabinin Acked-by: Olof Johansson Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

locking/lockdep: Fix debug_locks off performance problem

2018-11-13T19:16:48+00:00

[ 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 Cc: Andrew Morton Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Will Deacon Link: http://lkml.kernel.org/r/1539913518-15598-1-git-send-email-longman@redhat.com Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

test_bpf: Fix testing with CONFIG_BPF_JIT_ALWAYS_ON=y on other arches

2018-11-10T15:42:54+00:00

[ 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 Reviewed-by: Yonghong Song Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin

rhashtable: add schedule points

2018-10-18T07:13:24+00:00

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 Acked-by: Herbert Xu Signed-off-by: David S. Miller (cherry picked from commit ae6da1f503abb5a5081f9f6c4a6881de97830f3e) Signed-off-by: Greg Kroah-Hartman

scsi: klist: Make it safe to use klists in atomic context

2018-10-04T00:01:45+00:00

[ 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); 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 Cc: Martin K. Petersen Cc: James Bottomley Acked-by: Greg Kroah-Hartman Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman