Re: [PATCH 2/9] mm/damon/ops-common: align MMU notifier range when clearing PTE young bit

[sashiko-bot@kernel.org]

> From: "Shubhang Kaushik (Ampere)" <sh@gentwo.org>
> 
> DAMON selects a byte-granular sampling address.  damon_ptep_mkold()
> clears the young bit of the PTE covering that address, but passes the
> unaligned range [addr, addr + PAGE_SIZE) to MMU notifiers.
> 
> For an unaligned address, that range extends into the following page.
> KVM ages every guest page intersecting the notifier range, so it can age
> a secondary mapping for the following page although DAMON cleared only
> the sampled page's primary PTE.
> 
> Align the address before both the primary PTE operation and the
> MMU notifier call so that they cover the same page.
> 
> Fixes: 3f49584b262c ("mm/damon: implement primitives for the virtual memory address spaces")
> Signed-off-by: Shubhang Kaushik (Ampere) <sh@gentwo.org>
> Reviewed-by: Aveline Noir <jm5905938@gmail.com>
> Tested-by: Aveline Noir <jm5905938@gmail.com>
> Reviewed-by: SJ Park <sj@kernel.org>
> Signed-off-by: SJ Park <sj@kernel.org>

Sashiko has reviewed this patch and found no issues.

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