Re: [PATCH v3 0/2] arm64: ptdump flush fixes

From: Marc Zyngier

Date: Sun Aug 23 2026 - 06:11:11 EST


On Fri, 14 Aug 2026 23:24:56 +0100,
Wei-Lin Chang <weilin.chang@xxxxxxx> wrote:
>
> Hi,
>
> This series fixes two problems around ptdumps:
>
> 1. note_page_flush(), which flushes out the last row of ptdumps, does
> not account for address spaces that have IA < 64. Other than making
> the last region extremely huge, the attributes of the last region
> within the address spaces appear to extend all the way to 1 << 64.
>
> 2. KVM/arm64's stage-2 ptdump missed calling note_page_flush().
>
> To address Will's comment [1], I have created an end_address field for
> struct ptdump_pg_state, and initialized it with the end address of the
> ptdumps. It follows the same convention as the last range->end:
> exclusive end, except for the case where the address space ends at
> 1 << 64. In that case it is set as ULONG_MAX.
>
> Caching the end address avoids duplicating the range iteration in
> note_page_flush(), at the cost of duplicating state in ptdump_pg_state.
>
> Series is based on v7.2-rc5.

Reviewed-by: Marc Zyngier <maz@xxxxxxxxxx>

Will, if you're OK with patch #1, do you want the whole thing to go
via the arm64 or the kvmarm tree?

Thanks,

M.

--
Jazz isn't dead. It just smells funny.