On Thu, Nov 23, 2017 at 08:23:08PM +0800, Yisheng Xie wrote: > 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 MAX_SCAN_SIZE. > > Suggested-by: Catalin Marinas <catalin.marinas@xxxxxxx> > Signed-off-by: Yisheng Xie <xieyisheng1@xxxxxxxxxx> Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx> -- 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>