Hi Andrey, On 12/3/20 4:15 PM, Andrey Konovalov wrote: > On Thu, Dec 3, 2020 at 5:04 PM Qian Cai <qcai@xxxxxxxxxx> wrote: >> >> On Thu, 2020-11-26 at 10:13 +0530, vjitta@xxxxxxxxxxxxxx wrote: >>> From: Yogesh Lal <ylal@xxxxxxxxxxxxxx> >>> >>> Add a kernel parameter stack_hash_order to configure STACK_HASH_SIZE. >>> >>> Aim is to have configurable value for STACK_HASH_SIZE, so that one >>> can configure it depending on usecase there by reducing the static >>> memory overhead. >>> >>> One example is of Page Owner, default value of STACK_HASH_SIZE lead >>> stack depot to consume 8MB of static memory. Making it configurable >>> and use lower value helps to enable features like CONFIG_PAGE_OWNER >>> without any significant overhead. >>> >>> Suggested-by: Minchan Kim <minchan@xxxxxxxxxx> >>> Signed-off-by: Yogesh Lal <ylal@xxxxxxxxxxxxxx> >>> Signed-off-by: Vijayanand Jitta <vjitta@xxxxxxxxxxxxxx> >> >> Reverting this commit on today's linux-next fixed boot crash with KASAN. >> >> .config: >> https://cailca.coding.net/public/linux/mm/git/files/master/x86.config >> https://cailca.coding.net/public/linux/mm/git/files/master/arm64.config > > Vincenzo, Catalin, looks like this is the cause of the crash you > observed. Reverting this commit from next-20201203 fixes KASAN for me. > > Thanks for the report Qian! > Thank you for this. I will try and let you know as well. >>> --- >>> lib/stackdepot.c | 27 ++++++++++++++++++++++----- >>> 1 file changed, 22 insertions(+), 5 deletions(-) >>> >>> diff --git a/lib/stackdepot.c b/lib/stackdepot.c >>> index 81c69c0..ce53598 100644 >>> --- a/lib/stackdepot.c >>> +++ b/lib/stackdepot.c >>> @@ -141,14 +141,31 @@ static struct stack_record *depot_alloc_stack(unsigned long *entries, int size, >>> return stack; >>> } >>> >>> -#define STACK_HASH_ORDER 20 >>> -#define STACK_HASH_SIZE (1L << STACK_HASH_ORDER) >>> +static unsigned int stack_hash_order = 20; >>> +#define STACK_HASH_SIZE (1L << stack_hash_order) >>> #define STACK_HASH_MASK (STACK_HASH_SIZE - 1) >>> #define STACK_HASH_SEED 0x9747b28c >>> >>> -static struct stack_record *stack_table[STACK_HASH_SIZE] = { >>> - [0 ... STACK_HASH_SIZE - 1] = NULL >>> -}; >>> +static struct stack_record **stack_table; >>> + >>> +static int __init setup_stack_hash_order(char *str) >>> +{ >>> + kstrtouint(str, 0, &stack_hash_order); >>> + return 0; >>> +} >>> +early_param("stack_hash_order", setup_stack_hash_order); >>> + >>> +static int __init init_stackdepot(void) >>> +{ >>> + int i; >>> + >>> + stack_table = kvmalloc(sizeof(struct stack_record *) * STACK_HASH_SIZE, GFP_KERNEL); >>> + for (i = 0; i < STACK_HASH_SIZE; i++) >>> + stack_table[i] = NULL; >>> + return 0; >>> +} >>> + >>> +early_initcall(init_stackdepot); >>> >>> /* Calculate hash for a stack */ >>> static inline u32 hash_stack(unsigned long *entries, unsigned int size) >> >> -- >> You received this message because you are subscribed to the Google Groups "kasan-dev" group. >> To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@xxxxxxxxxxxxxxxx. >> To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/7733019eb8c506eee8d29e380aae683a8972fd19.camel%40redhat.com. -- Regards, Vincenzo
