The patch titled Subject: gcov: fix softlockups has been removed from the -mm tree. Its filename was gcov-fix-softlockups.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx> Subject: gcov: fix softlockups gcov profiling if enabled with other heavy compile-time instrumentation like KASan could trigger following softlockups: [ 72.460059] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1] [ 72.460068] Modules linked in: [ 72.460068] irq event stamp: 22823276 [ 72.460068] hardirqs last enabled at (22823275): [<ffffffff86e8d10d>] mutex_lock_nested+0x7d9/0x930 [ 72.460068] hardirqs last disabled at (22823276): [<ffffffff86e9521d>] apic_timer_interrupt+0x6d/0x80 [ 72.460068] softirqs last enabled at (22823172): [<ffffffff811ed969>] __do_softirq+0x4db/0x729 [ 72.460068] softirqs last disabled at (22823167): [<ffffffff811edfcf>] irq_exit+0x7d/0x15b [ 72.460068] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 3.19.0-05245-gbb33326-dirty #3 [ 72.460068] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5.1-0-g8936dbb-20141113_115728-nilsson.home.kraxel.org 04/01/2014 [ 72.460068] task: ffff88006cba8000 ti: ffff88006cbb0000 task.ti: ffff88006cbb0000 [ 72.460068] RIP: 0010:[<ffffffff8146822a>] [<ffffffff8146822a>] kasan_mem_to_shadow+0x1e/0x1f [ 72.460068] RSP: 0000:ffff88006cbb3cb0 EFLAGS: 00000207 [ 72.460068] RAX: fffffbfff1331380 RBX: ffffffff81468fc2 RCX: ffff88006d600006 [ 72.460068] RDX: dffffc0000000000 RSI: ffffffff89989bfa RDI: 1ffffffff1331380 [ 72.460068] RBP: ffff88006cbb3cf8 R08: 00000000037178af R09: 0000000003714ae1 [ 72.460068] R10: ffffed000c8d0b1f R11: 00000000000000cf R12: ffffffff8d8c2ba0 [ 72.460068] R13: ffff88006d640780 R14: ffffffff81269ad5 R15: ffff88006cbb3c58 [ 72.460068] FS: 0000000000000000(0000) GS:ffff88006d600000(0000) knlGS:0000000000000000 [ 72.460068] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 72.460068] CR2: 0000000000000000 CR3: 000000000a229000 CR4: 00000000000006f0 [ 72.460068] Stack: [ 72.460068] ffffffff81468a10 dffffc0000000000 ffffffff8abcfac0 ffff88006cbb3d28 [ 72.460068] ffffffff81468fc2 ffff88006cbb3d38 ffffffff81468fc2 dffffc0000000000 [ 72.460068] ffffffff89989c05 ffff88006cbb3d28 ffffffff8212fea0 ffff880063049398 [ 72.460068] Call Trace: [ 72.460068] [<ffffffff81468a10>] ? __asan_load1+0x66/0xbb [ 72.460068] [<ffffffff81468fc2>] ? __asan_load8+0x6d/0x10c [ 72.460068] [<ffffffff81468fc2>] ? __asan_load8+0x6d/0x10c [ 72.460068] [<ffffffff8212fea0>] strcmp+0x28/0x70 [ 72.460068] [<ffffffff813228af>] get_node_by_name+0x66/0x99 [ 72.460068] [<ffffffff81323879>] gcov_event+0x4f/0x69e [ 72.460068] [<ffffffff86e90477>] ? mutex_unlock+0x15/0x1e [ 72.460068] [<ffffffff8ca18cb9>] ? gcov_persist_setup+0x77/0x77 [ 72.460068] [<ffffffff8ca18cb9>] ? gcov_persist_setup+0x77/0x77 [ 72.460068] [<ffffffff813227a6>] gcov_enable_events+0x54/0x7b [ 72.460068] [<ffffffff8ca18db1>] gcov_fs_init+0xf8/0x134 [ 72.460068] [<ffffffff810022ca>] do_one_initcall+0x1b2/0x288 [ 72.460068] [<ffffffff81468fc2>] ? __asan_load8+0x6d/0x10c [ 72.460068] [<ffffffff8c9c8f02>] kernel_init_freeable+0x467/0x580 [ 72.460068] [<ffffffff86dd9a48>] ? rest_init+0x23b/0x23b [ 72.460068] [<ffffffff86dd9a5d>] kernel_init+0x15/0x18b [ 72.460068] [<ffffffff86e93f3c>] ret_from_fork+0x7c/0xb0 [ 72.460068] [<ffffffff86dd9a48>] ? rest_init+0x23b/0x23b [ 72.460068] Code: ff 48 ff 05 61 ec c2 0c 48 89 e5 5d c3 55 48 c1 ef 03 48 ba 00 00 00 00 00 fc ff df 48 8d 04 17 48 ff 05 da f5 c2 0c 48 89 e5 5d <c3> 55 48 ff 05 f5 fe c2 0c 48 89 e5 5d c3 55 48 ff 05 f0 fe c2 [ 72.460068] Kernel panic - not syncing: softlockup: hung tasks Fix this by sticking cond_resched() in gcov_enable_events(). Signed-off-by: Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx> Reported-by: Fengguang Wu <fengguang.wu@xxxxxxxxx> Cc: Peter Oberparleiter <oberpar@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/gcov/base.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff -puN kernel/gcov/base.c~gcov-fix-softlockups kernel/gcov/base.c --- a/kernel/gcov/base.c~gcov-fix-softlockups +++ a/kernel/gcov/base.c @@ -18,6 +18,7 @@ #include <linux/init.h> #include <linux/module.h> #include <linux/mutex.h> +#include <linux/sched.h> #include "gcov.h" static int gcov_events_enabled; @@ -107,8 +108,10 @@ void gcov_enable_events(void) gcov_events_enabled = 1; /* Perform event callback for previously registered entries. */ - while ((info = gcov_info_next(info))) + while ((info = gcov_info_next(info))) { gcov_event(GCOV_ADD, info); + cond_resched(); + } mutex_unlock(&gcov_lock); } _ Patches currently in -mm which might be from a.ryabinin@xxxxxxxxxxx are origin.patch linux-next.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html