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

[Mark Rutland]

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.

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

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