Re: [PATCH 0/7] arm64: hibernate: dust off the suspend/cleanup rework

[Bradley Morgan <brads@mainlining.org>]

On 2 September 2026 14:50:22 BST, Mark Rutland <mark.rutland@arm.com>
wrote:
>On Tue, Aug 25, 2026 at 08:58:32PM +0000, Bradley Morgan wrote:
>> This comes out of the hibernate resume discussion where Will asked if
>> the restored kernel's hyp vectors are reinstalled before we come back
>> from swsusp_arch_suspend() and free the reserved pages. Rather than
>> answer with a one off fix, this series reworks resume to look like a
>> resume from idle, which makes the answer fall out on its own.
>> 
>> The series leans on Mark Rutland's old work for inspiration, he had the
>> same end goal in a branch from back then:
>> 
>>  
>https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git/log/?h=arm64/suspend/cleanup
>
>Most of the series seems to be a rebased of those patches, just with
>paraphrased commit messages and my S-o-B lines dropped. As commented on
>patch 4, I do not think that is appropriate.

Same question as patch 2

If you want your S-O-B added, ok fine, but yeah.

Do you think this series itself is good? 

>
>I'll take a more in-depth look shortly.

thanks!

>
>Catalin, Will, for the moment please do not pick these up.
>
>Mark.
>
>> The short answer to the question: yes, but only because the rework makes
>> resume look like a resume from idle. We enter cpu_resume() at the
>highest
>> available EL with the MMU off, and the resumed kernel installs its own
>> hyp stub vectors into VBAR_EL2 through init_kernel_el() before anything
>> else runs, so by the time swsusp_free() releases the trans_pgd copies
>> nothing points at them anymore.
>> 
>> The series is structured so the first patch stands alone as a stable
>> worthy fix for the missing hvc arguments. The rest is the cleanup: the
>> stale init_kernel_el() comment gets corrected, MTE tag pages get freed
>> after save instead of leaking on failed hibernates, the fragile
>> _cpu_resume() calling convention gets split, and the last patch reworks
>> hibernate to use the regular cpu_resume() logic end to end.
>> 
>> Everything object compiles and passes checkpatch and sparse. I could not
>> boot or run a hibernate cycle on real hardware here, so that still wants
>> doing before anyone gets excited.
>> 
>> Bradley Morgan (7):
>>   arm64: hibernate: pass HVC_SET_VECTORS args to the resume hvc
>>   arm64: head: correct comment for init_kernel_el()
>>   arm64: hibernate: free MTE tag pages after saving
>>   arm64: hibernate: fix _cpu_resume() calling convention
>>   arm64: hibernate: use dcache_by_myline_op
>>   arm64: hibernate: only clean to PoC
>>   arm64: hibernate: use regular cpu_resume() logic
>> 
>>  arch/arm64/include/asm/suspend.h  |  1 -
>>  arch/arm64/kernel/head.S          |  6 +--
>>  arch/arm64/kernel/hibernate-asm.S | 87 +++++++++++++++++++------------
>>  arch/arm64/kernel/hibernate.c     | 66 +++++++++++------------
>>  arch/arm64/kernel/sleep.S         |  6 +--
>>  5 files changed, 88 insertions(+), 78 deletions(-)
>> 
>> -- 
>> 2.47.3

--- Thanks!
https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/