Re: [PATCH mm-hotfixses] Revert "mm: limit filemap_fault readahead to VMA boundaries"

[Matthew Wilcox]

On Fri, Jun 19, 2026 at 12:28:51PM +0100, Lorenzo Stoakes wrote:
> This reverts commit 7b32f64bc512b40b268776c5ac4d354b325b3197.
> 
> This patch caused a significant performance regression, so revert it, and
> we can determine whether the approach is sensible or not moving forwards,
> and if so how to avoid this.
> 
> There was a merge conflict with commit de97ae6222c1 ("mm/readahead: no
> PG_readahead on EOF"), care was taken to ensure that the revert retained the
> behaviour of this patch and cleanly reverts commit 7b32f64bc512 ("mm: limit
> filemap_fault readahead to VMA boundaries") only.
> 
> Fixes: 7b32f64bc512 ("mm: limit filemap_fault readahead to VMA boundaries")
> Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-lkp/202606181547.617a6967-lkp@xxxxxxxxx
> Signed-off-by: Lorenzo Stoakes <ljs@xxxxxxxxxx>

Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>