This is a note to let you know that I've just added the patch titled ia64: mca: allocate early mca with GFP_ATOMIC to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ia64-mca-allocate-early-mca-with-gfp_atomic.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit f98a65cb3bc4c8905dc1e39ebc2d6c6b6302285e Author: Sergei Trofimovich <slyfox@xxxxxxxxxx> Date: Wed Mar 24 21:37:38 2021 -0700 ia64: mca: allocate early mca with GFP_ATOMIC [ Upstream commit f2a419cf495f95cac49ea289318b833477e1a0e2 ] The sleep warning happens at early boot right at secondary CPU activation bootup: smp: Bringing up secondary CPUs ... BUG: sleeping function called from invalid context at mm/page_alloc.c:4942 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.12.0-rc2-00007-g79e228d0b611-dirty #99 .. Call Trace: show_stack+0x90/0xc0 dump_stack+0x150/0x1c0 ___might_sleep+0x1c0/0x2a0 __might_sleep+0xa0/0x160 __alloc_pages_nodemask+0x1a0/0x600 alloc_page_interleave+0x30/0x1c0 alloc_pages_current+0x2c0/0x340 __get_free_pages+0x30/0xa0 ia64_mca_cpu_init+0x2d0/0x3a0 cpu_init+0x8b0/0x1440 start_secondary+0x60/0x700 start_ap+0x750/0x780 Fixed BSP b0 value from CPU 1 As I understand interrupts are not enabled yet and system has a lot of memory. There is little chance to sleep and switch to GFP_ATOMIC should be a no-op. Link: https://lkml.kernel.org/r/20210315085045.204414-1-slyfox@xxxxxxxxxx Signed-off-by: Sergei Trofimovich <slyfox@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/ia64/kernel/mca.c b/arch/ia64/kernel/mca.c index bf2cb9294795..d96c68122eae 100644 --- a/arch/ia64/kernel/mca.c +++ b/arch/ia64/kernel/mca.c @@ -1851,7 +1851,7 @@ ia64_mca_cpu_init(void *cpu_data) data = mca_bootmem(); first_time = 0; } else - data = (void *)__get_free_pages(GFP_KERNEL, + data = (void *)__get_free_pages(GFP_ATOMIC, get_order(sz)); if (!data) panic("Could not allocate MCA memory for cpu %d\n",