lkml.org 
[lkml]   [2022]   [Sep]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [RFC PATCH RESEND 19/28] mm: disallow do_swap_page to handle page faults under VMA lock
From
Le 01/09/2022 à 19:35, Suren Baghdasaryan a écrit :
> Due to the possibility of do_swap_page dropping mmap_lock, abort fault
> handling under VMA lock and retry holding mmap_lock. This can be handled
> more gracefully in the future.
>
> Signed-off-by: Suren Baghdasaryan <surenb@google.com>

Reviewed-by: Laurent Dufour <laurent.dufour@fr.ibm.com>

> ---
> mm/memory.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/mm/memory.c b/mm/memory.c
> index 9ac9944e8c62..29d2f49f922a 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -3738,6 +3738,11 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
> vm_fault_t ret = 0;
> void *shadow = NULL;
>
> + if (vmf->flags & FAULT_FLAG_VMA_LOCK) {
> + ret = VM_FAULT_RETRY;
> + goto out;
> + }
> +
> if (!pte_unmap_same(vmf))
> goto out;
>

\
 
 \ /
  Last update: 2022-09-09 16:28    [W:0.376 / U:0.448 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site