Yong-Taek Lee 9980c4251f printk: use kvmalloc instead of kmalloc for devkmsg_user ... Size of struct devkmsg_user increased to 16784 by commit 896fbe20b4 ("printk: use the lockless ringbuffer") so order3(32kb) is needed for kmalloc. Under stress conditions the kernel may temporary fail to allocate 32k with kmalloc. Use kvmalloc instead of kmalloc to aviod this issue. qseecomd invoked oom-killer: gfp_mask=0x40cc0(GFP_KERNEL|__GFP_COMP), order=3, oom_score_adj=-1000 Call trace: dump_backtrace+0x0/0x34c dump_stack_lvl+0xd4/0x16c dump_header+0x5c/0x338 out_of_memory+0x374/0x4cc __alloc_pages_slowpath+0xbc8/0x1130 __alloc_pages_nodemask+0x170/0x1b0 kmalloc_order+0x5c/0x24c devkmsg_open+0x1f4/0x558 memory_open+0x94/0xf0 chrdev_open+0x288/0x3dc do_dentry_open+0x2b4/0x618 path_openat+0xce4/0xfa8 do_filp_open+0xb0/0x164 do_sys_openat2+0xa8/0x264 __arm64_sys_openat+0x70/0xa0 el0_svc_common+0xc4/0x270 el0_svc+0x34/0x9c el0_sync_handler+0x88/0xf0 el0_sync+0x1bc/0x200 DMA32: 4521*4kB (UMEC) 1377*8kB (UMECH) 73*16kB (UM) 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 30268kB Normal: 2490*4kB (UMEH) 277*8kB (UMH) 27*16kB (UH) 1*32kB (H) 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 12640kB Signed-off-by: Yong-Taek Lee <ytk.lee@samsung.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20210830071701epcms1p70f72ae10940bc407a3c33746d20da771@epcms1p7		2021-09-07 14:57:01 +02:00
..
braille.c	printk: Replace strncmp() with str_has_prefix()	2019-08-16 09:54:08 +02:00
braille.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
console_cmdline.h	printk: Fix preferred console selection with multiple matches	2020-02-18 09:34:42 +01:00
index.c	printk/index: Fix -Wunused-function warning	2021-08-27 16:42:44 +02:00
internal.h	Merge branch 'rework/printk_safe-removal' into for-linus	2021-08-30 16:36:10 +02:00
Makefile	printk: Userspace format indexing support	2021-07-19 11:57:48 +02:00
printk_ringbuffer.c	Merge branch 'printk-rework' into for-linus	2021-01-21 16:06:21 +01:00
printk_ringbuffer.h	printk: rectify kernel-doc for prb_rec_init_wr()	2021-01-26 11:17:51 +01:00
printk_safe.c	printk: remove NMI tracking	2021-07-26 15:09:44 +02:00
printk.c	printk: use kvmalloc instead of kmalloc for devkmsg_user	2021-09-07 14:57:01 +02:00