The first kmemleak_scan() after boot would trigger a crash below because kernel_init free_initmem mem_encrypt_free_decrypted_mem free_init_pages
unmapped some memory inside the .bss. BUG: unable to handle kernel paging request at ffffffffbd402000 CPU: 12 PID: 325 Comm: kmemleak Not tainted 5.1.0-rc4+ #4 RIP: 0010:scan_block+0x58/0x160 Call Trace: scan_gray_list+0x1d9/0x280 kmemleak_scan+0x485/0xad0 kmemleak_scan_thread+0x9f/0xc4 kthread+0x1d2/0x1f0 ret_from_fork+0x35/0x40 Signed-off-by: Qian Cai <c...@lca.pw> --- arch/x86/mm/mem_encrypt.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 385afa2b9e17..614ab156024f 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -18,6 +18,7 @@ #include <linux/dma-direct.h> #include <linux/swiotlb.h> #include <linux/mem_encrypt.h> +#include <linux/kmemleak.h> #include <asm/tlbflush.h> #include <asm/fixmap.h> @@ -369,6 +370,11 @@ void __init mem_encrypt_free_decrypted_mem(void) } } + /* + * Inform kmemleak about the hole in the .bss section since the + * corresponding pages will be unmapped with DEBUG_PAGEALLOC=y. + */ + kmemleak_free_part((void *)vaddr, vaddr_end - vaddr); free_init_pages("unused decrypted", vaddr, vaddr_end); } -- 2.17.2 (Apple Git-113)