projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| 12eb7899 GKH |
1 | From foo@baz Thu Oct 4 12:38:43 PDT 2018 |
| 2 | From: Will Deacon <will.deacon@arm.com> | |
| 3 | Date: Thu, 30 Aug 2018 13:52:38 -0700 | |
| 4 | Subject: ARC: atomics: unbork atomic_fetch_##op() | |
| 5 | ||
| 6 | From: Will Deacon <will.deacon@arm.com> | |
| 7 | ||
| 8 | [ Upstream commit 3fcbb8260a87efb691d837e8cd24e81f65b3eb70 ] | |
| 9 | ||
| 10 | In 4.19-rc1, Eugeniy reported weird boot and IO errors on ARC HSDK | |
| 11 | ||
| 12 | | INFO: task syslogd:77 blocked for more than 10 seconds. | |
| 13 | | Not tainted 4.19.0-rc1-00007-gf213acea4e88 #40 | |
| 14 | | "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this | |
| 15 | | message. | |
| 16 | | syslogd D 0 77 76 0x00000000 | |
| 17 | | | |
| 18 | | Stack Trace: | |
| 19 | | __switch_to+0x0/0xac | |
| 20 | | __schedule+0x1b2/0x730 | |
| 21 | | io_schedule+0x5c/0xc0 | |
| 22 | | __lock_page+0x98/0xdc | |
| 23 | | find_lock_entry+0x38/0x100 | |
| 24 | | shmem_getpage_gfp.isra.3+0x82/0xbfc | |
| 25 | | shmem_fault+0x46/0x138 | |
| 26 | | handle_mm_fault+0x5bc/0x924 | |
| 27 | | do_page_fault+0x100/0x2b8 | |
| 28 | | ret_from_exception+0x0/0x8 | |
| 29 | ||
| 30 | He bisected to 84c6591103db ("locking/atomics, | |
| 31 | asm-generic/bitops/lock.h: Rewrite using atomic_fetch_*()") | |
| 32 | ||
| 33 | This commit however only unmasked the real issue introduced by commit | |
| 34 | 4aef66c8ae9 ("locking/atomic, arch/arc: Fix build") which missed the | |
| 35 | retry-if-scond-failed branch in atomic_fetch_##op() macros. | |
| 36 | ||
| 37 | The bisected commit started using atomic_fetch_##op() macros for building | |
| 38 | the rest of atomics. | |
| 39 | ||
| 40 | Fixes: 4aef66c8ae9 ("locking/atomic, arch/arc: Fix build") | |
| 41 | Reported-by: Eugeniy Paltsev <paltsev@synopsys.com> | |
| 42 | Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> | |
| 43 | Signed-off-by: Will Deacon <will.deacon@arm.com> | |
| 44 | Signed-off-by: Vineet Gupta <vgupta@synopsys.com> | |
| 45 | [vgupta: wrote changelog] | |
| 46 | Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> | |
| 47 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 48 | --- | |
| 49 | arch/arc/include/asm/atomic.h | 2 +- | |
| 50 | 1 file changed, 1 insertion(+), 1 deletion(-) | |
| 51 | ||
| 52 | --- a/arch/arc/include/asm/atomic.h | |
| 53 | +++ b/arch/arc/include/asm/atomic.h | |
| 54 | @@ -84,7 +84,7 @@ static inline int atomic_fetch_##op(int | |
| 55 | "1: llock %[orig], [%[ctr]] \n" \ | |
| 56 | " " #asm_op " %[val], %[orig], %[i] \n" \ | |
| 57 | " scond %[val], [%[ctr]] \n" \ | |
| 58 | - " \n" \ | |
| 59 | + " bnz 1b \n" \ | |
| 60 | : [val] "=&r" (val), \ | |
| 61 | [orig] "=&r" (orig) \ | |
| 62 | : [ctr] "r" (&v->counter), \ |