On Tue, Apr 4, 2023 at 1:50 PM xiaosong.ma <Xiaosong.Ma@xxxxxxxxxx> wrote: > > when we debug with slub_debug_on, the following backtraces show dump_page > will show wrong info when the bad page is non-NULL mapping and page->mapping > is 0x80000000000 so do virt_addr valid check is needed when dump mapping page. > > crash_arm64> bt > PID: 232 TASK: ffffff80e8c2c340 CPU: 0 COMMAND: "Binder:232_2" > #0 [ffffffc013e5b080] sysdump_panic_event$b2bce43a479f4f7762201bfee02d7889 at ffffffc0108d7c2c > #1 [ffffffc013e5b0c0] atomic_notifier_call_chain at ffffffc010300228 > #2 [ffffffc013e5b2c0] panic at ffffffc0102c926c > #3 [ffffffc013e5b370] die at ffffffc010267670 > #4 [ffffffc013e5b3a0] die_kernel_fault at ffffffc0102808a4 > #5 [ffffffc013e5b3d0] __do_kernel_fault at ffffffc010280820 > #6 [ffffffc013e5b410] do_bad_area at ffffffc01028059c > #7 [ffffffc013e5b440] do_translation_fault$4df5decbea5d08a63349aa36f07426b2 at ffffffc0111149c8 > #8 [ffffffc013e5b470] do_mem_abort at ffffffc0100a4488 > #9 [ffffffc013e5b5e0] el1_ia at ffffffc0100a6c00 > #10 [ffffffc013e5b5f0] __dump_page at ffffffc0104beecc > #11 [ffffffc013e5b630] bad_page at ffffffc0104e6ffc > #12 [ffffffc013e5b820] rmqueue_bulk at ffffffc0104e9128 > #13 [ffffffc013e5b950] rmqueue at ffffffc0104e7c3c > #14 [ffffffc013e5b9c0] get_page_from_freelist at ffffffc0104e3e3c > #15 [ffffffc013e5ba50] __alloc_pages_nodemask at ffffffc0104e3a7c > #16 [ffffffc013e5bac0] pagecache_get_page at ffffffc01047d0e4 > #17 [ffffffc013e5bb20] grab_cache_page_write_begin at ffffffc010480e3c > #18 [ffffffc013e5bb50] block_write_begin at ffffffc010586204 > #19 [ffffffc013e5bb90] blkdev_write_begin$75b353f60767e771433fc3b19ba260ab at ffffffc01058cc48 > #20 [ffffffc013e5bc00] generic_perform_write at ffffffc010480f1c > #21 [ffffffc013e5bc60] __generic_file_write_iter at ffffffc01048115c > #22 [ffffffc013e5bcf0] blkdev_write_iter at ffffffc01058c0a8 > #23 [ffffffc013e5bda0] __vfs_write at ffffffc01052d808 > #24 [ffffffc013e5bdd0] vfs_write at ffffffc01052da5c > #25 [ffffffc013e5be30] __arm64_sys_pwrite64 at ffffffc01052e09c > #26 [ffffffc013e5be60] el0_svc_common at ffffffc010272224 > #27 [ffffffc013e5bea0] el0_svc_handler at ffffffc010272148 > #28 [ffffffc013e5bff0] el0_svc at ffffffc0100a7ec4 > > Signed-off-by: xiaosong.ma <Xiaosong.Ma@xxxxxxxxxx> > --- > mm/debug.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/debug.c b/mm/debug.c > index 7f8e5f7..da61172 100644 > --- a/mm/debug.c > +++ b/mm/debug.c > @@ -109,7 +109,7 @@ static void __dump_page(struct page *page) > type = "ksm "; > else if (PageAnon(page)) > type = "anon "; > - else if (mapping) > + else if (mapping && virt_addr_valid(mapping)) could be else if (virt_addr_valid(mapping)) > dump_mapping(mapping); > BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1); > > -- > 1.9.1
