kmemleak_scan will scan struct page for each node and it can be really large and resulting in a soft lockup. We have seen a soft lockup when do scan while compile kernel: [ 220.561051] watchdog: BUG: soft lockup - CPU#53 stuck for 22s! [bash:10287] [...] [ 220.753837] Call Trace: [ 220.756296] kmemleak_scan+0x21a/0x4c0 [ 220.760034] kmemleak_write+0x312/0x350 [ 220.763866] ? do_wp_page+0x147/0x4c0 [ 220.767521] full_proxy_write+0x5a/0xa0 [ 220.771351] __vfs_write+0x33/0x150 [ 220.774833] ? __inode_security_revalidate+0x4c/0x60 [ 220.779782] ? selinux_file_permission+0xda/0x130 [ 220.784479] ? _cond_resched+0x15/0x30 [ 220.788221] vfs_write+0xad/0x1a0 [ 220.791529] SyS_write+0x52/0xc0 [ 220.794758] do_syscall_64+0x61/0x1a0 [ 220.798411] entry_SYSCALL64_slow_path+0x25/0x25 Fix this by adding cond_resched every 1024 pages. Signed-off-by: Yisheng Xie <xieyisheng1@xxxxxxxxxx> --- mm/kmemleak.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/kmemleak.c b/mm/kmemleak.c index e4738d5..e9f2e86 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -1523,6 +1523,8 @@ static void kmemleak_scan(void) if (page_count(page) == 0) continue; scan_block(page, page + 1, NULL); + if (!(pfn % 1024)) + cond_resched(); } } put_online_mems(); -- 1.7.12.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
