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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-18 09:04:17 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-18 09:04:17 -0700 |
| commit | e0ed1c22d480a3b5ec5fce4e5399cf4481da95a6 (patch) | |
| tree | f8750b76d55bcfe6c0d81678d2d87ccf92ad9e62 | |
| parent | 50276c9abb9c236a359854f30eb8bb81fd14a22d (diff) | |
| parent | 5f43086bb9224987010460dcf3dee68fbd4f574d (diff) | |
| download | linux-e0ed1c22d480a3b5ec5fce4e5399cf4481da95a6.tar.gz | |
Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
"Two fixes:
- a file locks fix (missing critical section, bug introduced in this
merge window)
- an x86 down_write() stack frame annotation"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking, fs/locks: Add missing file_sem locks
locking/rwsem/x86: Add stack frame dependency for ____down_write()
| -rw-r--r-- | arch/x86/include/asm/rwsem.h | 6 | ||||
| -rw-r--r-- | fs/locks.c | 6 |
2 files changed, 10 insertions, 2 deletions
diff --git a/arch/x86/include/asm/rwsem.h b/arch/x86/include/asm/rwsem.h index 3d33a719f5c1d8..a34e0d4b957d63 100644 --- a/arch/x86/include/asm/rwsem.h +++ b/arch/x86/include/asm/rwsem.h @@ -103,8 +103,10 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem) ({ \ long tmp; \ struct rw_semaphore* ret; \ + register void *__sp asm(_ASM_SP); \ + \ asm volatile("# beginning down_write\n\t" \ - LOCK_PREFIX " xadd %1,(%3)\n\t" \ + LOCK_PREFIX " xadd %1,(%4)\n\t" \ /* adds 0xffff0001, returns the old value */ \ " test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t" \ /* was the active mask 0 before? */\ @@ -112,7 +114,7 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem) " call " slow_path "\n" \ "1:\n" \ "# ending down_write" \ - : "+m" (sem->count), "=d" (tmp), "=a" (ret) \ + : "+m" (sem->count), "=d" (tmp), "=a" (ret), "+r" (__sp) \ : "a" (sem), "1" (RWSEM_ACTIVE_WRITE_BIAS) \ : "memory", "cc"); \ ret; \ diff --git a/fs/locks.c b/fs/locks.c index ce93b416b490fa..22c5b4aa49611a 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1609,6 +1609,7 @@ int fcntl_getlease(struct file *filp) ctx = smp_load_acquire(&inode->i_flctx); if (ctx && !list_empty_careful(&ctx->flc_lease)) { + percpu_down_read_preempt_disable(&file_rwsem); spin_lock(&ctx->flc_lock); time_out_leases(inode, &dispose); list_for_each_entry(fl, &ctx->flc_lease, fl_list) { @@ -1618,6 +1619,8 @@ int fcntl_getlease(struct file *filp) break; } spin_unlock(&ctx->flc_lock); + percpu_up_read_preempt_enable(&file_rwsem); + locks_dispose_list(&dispose); } return type; @@ -2529,11 +2532,14 @@ locks_remove_lease(struct file *filp, struct file_lock_context *ctx) if (list_empty(&ctx->flc_lease)) return; + percpu_down_read_preempt_disable(&file_rwsem); spin_lock(&ctx->flc_lock); list_for_each_entry_safe(fl, tmp, &ctx->flc_lease, fl_list) if (filp == fl->fl_file) lease_modify(fl, F_UNLCK, &dispose); spin_unlock(&ctx->flc_lock); + percpu_up_read_preempt_enable(&file_rwsem); + locks_dispose_list(&dispose); } |