On 1/10/23 14:53, Oliver Sang wrote: > hi all, > > On Mon, Jan 09, 2023 at 10:01:15PM +0800, Oliver Sang wrote: >> >> On Fri, Jan 06, 2023 at 11:13:15AM +0100, Vlastimil Babka wrote: >> >> > And if the rate at the parent (has it increased thanks to the >> > DEBUG_PAGEALLOC?) is sufficient to bisect to the truly first bad commit. Thanks! >> >> got it. Thanks for suggestion! >> >> since 0af8489b02 is based on v6.1-rc2, we will test (both rectorture and boot) >> with same config upon v6.1-rc2 to see if it's really clean there. >> if so we will use dmesg.invalid_opcode:#[##] to trigger new bisect. >> >> will keep you updated. Thanks > > by more tests, we cannot make sure the v6.1-rc2 is clean, so we also checked > v6.1-rc1 and v6.0. from results, we have low confidence that we can make a > successful bisection based on them [1][2]. could you suggest? So am I reading it right, that the probleam appears to be introduced between v6.0 (0 failures) and v6.1-rc1 (>0 failures)? But agree that with such low incidence, it's hard to bisect. > a further information not sure if it's helpful, [1][2] are both i386 based. > we also tried to run boot tests on x86_64 upon commit 0af8489b02, whatever > with or without CONFIG_DEBUG_PAGEALLOC/CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT, > we never obseve similar issues (also run 999 times). Yeah it looks very much like something that manifests only on i386 (perhaps only in QEMU as well?) and never x86_64. What might be interesting then is v6.1-rc1 with further modified config to enabled CONFIG_SLUB_DEBUG and CONFIG_SLUB_DEBUG_ON. Maybe it will catch the culprit sooner. Or maybe it will obscure the bug instead, unfortunately. Thanks for all your effort! > [1] > boot results: > ========================================================================================= > compiler/kconfig/rootfs/sleep/tbox_group/testcase: > gcc-11/i386-randconfig-a012-20221226+CONFIG_DEBUG_PAGEALLOC+CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT/debian-11.1-i386-20220923.cgz/1/vm-snb/boot > > v6.0 v6.1-rc1 v6.1-rc2 56d5a2b9ba85a390473e86b4fe4 0af8489b0216fa1dd83e264bef8 > ---------------- --------------------------- --------------------------- --------------------------- --------------------------- > fail:runs %reproduction fail:runs %reproduction fail:runs %reproduction fail:runs %reproduction fail:runs > | | | | | | | | | > :999 0% 2:999 0% 1:999 1% 11:999 21% 208:999 dmesg.invalid_opcode:#[##] > :999 0% :999 0% :999 0% 2:999 5% 51:999 dmesg.kernel_BUG_at_include/linux/mm.h > :999 0% 1:999 0% :999 0% 4:999 4% 40:999 dmesg.kernel_BUG_at_include/linux/page-flags.h > :999 0% 1:999 0% 1:999 0% 4:999 11% 111:999 dmesg.kernel_BUG_at_lib/list_debug.c > :999 0% :999 0% :999 0% :999 0% 2:999 dmesg.kernel_BUG_at_mm/page_alloc.c > :999 0% :999 0% :999 0% 1:999 0% 3:999 dmesg.kernel_BUG_at_mm/usercopy.c > > [2] > rcutorture results: > ========================================================================================= > compiler/kconfig/rootfs/runtime/tbox_group/test/testcase/torture_type: > gcc-11/i386-randconfig-a012-20221226+CONFIG_DEBUG_PAGEALLOC+CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT/debian-11.1-i386-20220923.cgz/300s/vm-snb/default/rcutorture/tasks-tracing > > v6.0 v6.1-rc1 v6.1-rc2 56d5a2b9ba85a390473e86b4fe4 0af8489b0216fa1dd83e264bef8 > ---------------- --------------------------- --------------------------- --------------------------- --------------------------- > fail:runs %reproduction fail:runs %reproduction fail:runs %reproduction fail:runs %reproduction fail:runs > | | | | | | | | | > :999 0% 3:999 0% :999 1% 8:998 20% 200:999 dmesg.invalid_opcode:#[##] > :999 0% :999 0% :999 0% :998 5% 51:999 dmesg.kernel_BUG_at_include/linux/mm.h > :999 0% :999 0% :999 0% 3:998 4% 42:999 dmesg.kernel_BUG_at_include/linux/page-flags.h > :999 0% 3:999 0% :999 0% 4:998 10% 102:999 dmesg.kernel_BUG_at_lib/list_debug.c > :999 0% :999 0% :999 0% :998 0% 2:999 dmesg.kernel_BUG_at_mm/page_alloc.c > :999 0% :999 0% :999 0% 1:998 0% 3:999 dmesg.kernel_BUG_at_mm/usercopy.c > >> >> > >> >
