Re: [PATCHv4 2/2] mm: use stack_depot_early_init for kmemleak

From: Catalin Marinas
Date: Thu Jan 19 2023 - 05:13:46 EST


On Thu, Jan 19, 2023 at 09:22:25AM +0800, zhaoyang.huang wrote:
> From: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx>
>
> Mirsad report bellow error which caused by stack_depot_init failed in kvcalloc.
> Solve this by having stackdepot use stack_depot_early_init.
>
> On 1/4/23 17:08, Mirsad Goran Todorovac wrote:
> I hate to bring bad news again, but there seems to be a problem with the output of /sys/kernel/debug/kmemleak:
>
> [root@pc-mtodorov ~]# cat /sys/kernel/debug/kmemleak
> unreferenced object 0xffff951c118568b0 (size 16):
> comm "kworker/u12:2", pid 56, jiffies 4294893952 (age 4356.548s)
> hex dump (first 16 bytes):
> 6d 65 6d 73 74 69 63 6b 30 00 00 00 00 00 00 00 memstick0.......
> backtrace:
> [root@pc-mtodorov ~]#
>
> Apparently, backtrace of called functions on the stack is no longer printed with the list of memory leaks.
> This appeared on Lenovo desktop 10TX000VCR, with AlmaLinux 8.7 and BIOS version M22KT49A (11/10/2022)
> and 6.2-rc1 and 6.2-rc2 builds.
> This worked on 6.1 with the same CONFIG_KMEMLEAK=y and MGLRU enabled on a vanilla mainstream kernel
> from Mr. Torvalds' tree. I don't know if this is deliberate feature for some reason or a bug.
> Please find attached the config, lshw and kmemleak output.
>
> reported-by: Mirsad Todorovac <mirsad.todorovac@xxxxxxxxxxxx>
> suggested-by: Vlastimil Babka <vbabka@xxxxxxx>
> Signed-off-by: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx>

Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>