From: Jing Xia <jing.xia@xxxxxxxxxx> Subject: mm/mm_init.c: report kasan-tag information stored in page->flags The pageflags_layout_usage shows incorrect message by means of mminit_loglevel when Kasan runs in the mode of software tag-based enabled with CONFIG_KASAN_SW_TAGS. This patch corrects it and reports kasan-tag information. Link: http://lkml.kernel.org/r/1586929370-10838-1-git-send-email-jing.xia.mail@xxxxxxxxx Signed-off-by: Jing Xia <jing.xia@xxxxxxxxxx> Cc: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx> Cc: Orson Zhai <orson.zhai@xxxxxxxxxx> Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/mm_init.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) --- a/mm/mm_init.c~mm-init-report-kasan-tag-information-stored-in-page-flags +++ a/mm/mm_init.c @@ -67,26 +67,30 @@ void __init mminit_verify_pageflags_layo unsigned long or_mask, add_mask; shift = 8 * sizeof(unsigned long); - width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH - LAST_CPUPID_SHIFT; + width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH + - LAST_CPUPID_SHIFT - KASAN_TAG_WIDTH; mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths", - "Section %d Node %d Zone %d Lastcpupid %d Flags %d\n", + "Section %d Node %d Zone %d Lastcpupid %d Kasantag %d Flags %d\n", SECTIONS_WIDTH, NODES_WIDTH, ZONES_WIDTH, LAST_CPUPID_WIDTH, + KASAN_TAG_WIDTH, NR_PAGEFLAGS); mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts", - "Section %d Node %d Zone %d Lastcpupid %d\n", + "Section %d Node %d Zone %d Lastcpupid %d Kasantag %d\n", SECTIONS_SHIFT, NODES_SHIFT, ZONES_SHIFT, - LAST_CPUPID_SHIFT); + LAST_CPUPID_SHIFT, + KASAN_TAG_WIDTH); mminit_dprintk(MMINIT_TRACE, "pageflags_layout_pgshifts", - "Section %lu Node %lu Zone %lu Lastcpupid %lu\n", + "Section %lu Node %lu Zone %lu Lastcpupid %lu Kasantag %lu\n", (unsigned long)SECTIONS_PGSHIFT, (unsigned long)NODES_PGSHIFT, (unsigned long)ZONES_PGSHIFT, - (unsigned long)LAST_CPUPID_PGSHIFT); + (unsigned long)LAST_CPUPID_PGSHIFT, + (unsigned long)KASAN_TAG_PGSHIFT); mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodezoneid", "Node/Zone ID: %lu -> %lu\n", (unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT), _