linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Randy Dunlap <rdunlap@infradead.org>
To: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>,
	Andrew Morton <akpm@linux-foundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>,
	David Hildenbrand <david@redhat.com>,
	"Liam R . Howlett" <Liam.Howlett@oracle.com>,
	Vlastimil Babka <vbabka@suse.cz>, Mike Rapoport <rppt@kernel.org>,
	Suren Baghdasaryan <surenb@google.com>,
	Michal Hocko <mhocko@suse.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Jann Horn <jannh@google.com>, Pedro Falcato <pfalcato@suse.de>,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-doc@vger.kernel.org, linux-mm@kvack.org,
	linux-trace-kernel@vger.kernel.org,
	linux-kselftest@vger.kernel.org, Andrei Vagin <avagin@gmail.com>
Subject: Re: [PATCH 1/3] mm: introduce VM_MAYBE_GUARD and make visible for guard regions
Date: Wed, 29 Oct 2025 12:50:18 -0700	[thread overview]
Message-ID: <6c273611-e815-4a4a-822d-f6e55cec3810@infradead.org> (raw)
In-Reply-To: <7de40603015dee82970f5d37332a6d5af7532063.1761756437.git.lorenzo.stoakes@oracle.com>


On 10/29/25 9:50 AM, Lorenzo Stoakes wrote:

> diff --git a/mm/memory.c b/mm/memory.c
> index 4c3a7e09a159..a2c79ee43d68 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -1478,6 +1478,10 @@ vma_needs_copy(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma)
>  	if (src_vma->anon_vma)
>  		return true;
>  
> +	/* Guard regions have momdified page tables that require copying. */

	                      modified

> +	if (src_vma->vm_flags & VM_MAYBE_GUARD)
> +		return true;
> +
>  	/*
>  	 * Don't copy ptes where a page fault will fill them correctly.  Fork
>  	 * becomes much lighter when there are big shared or private readonly
-- 
~Randy


  reply	other threads:[~2025-10-29 19:50 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-10-29 16:50 [PATCH 0/3] introduce VM_MAYBE_GUARD and make it sticky Lorenzo Stoakes
2025-10-29 16:50 ` [PATCH 1/3] mm: introduce VM_MAYBE_GUARD and make visible for guard regions Lorenzo Stoakes
2025-10-29 19:50   ` Randy Dunlap [this message]
2025-10-30  8:13     ` Lorenzo Stoakes
2025-10-30  1:05   ` Suren Baghdasaryan
2025-10-30  8:22     ` Lorenzo Stoakes
2025-10-30 16:16   ` Pedro Falcato
2025-10-30 16:23     ` Lorenzo Stoakes
2025-10-30 16:31       ` Pedro Falcato
2025-10-30 16:43         ` Lorenzo Stoakes
2025-10-30 18:31           ` Vlastimil Babka
2025-10-30 18:47             ` Vlastimil Babka
2025-10-30 19:47               ` Lorenzo Stoakes
2025-10-30 21:48                 ` Vlastimil Babka
2025-10-31 23:12                   ` Suren Baghdasaryan
2025-11-03  9:34                     ` Lorenzo Stoakes
2025-11-05 19:48               ` Lorenzo Stoakes
2025-11-06  7:34                 ` Vlastimil Babka
2025-10-30 19:16             ` Lorenzo Stoakes
2025-10-30 19:37               ` Lorenzo Stoakes
2025-10-29 16:50 ` [PATCH 2/3] mm: implement sticky, copy on fork VMA flags Lorenzo Stoakes
2025-10-30  4:35   ` Suren Baghdasaryan
2025-10-30  8:25     ` Lorenzo Stoakes
2025-10-30 16:25   ` Pedro Falcato
2025-10-30 16:34     ` Lorenzo Stoakes
2025-10-29 16:50 ` [PATCH 3/3] selftests/mm/guard-regions: add smaps visibility test Lorenzo Stoakes
2025-10-30  4:40   ` Suren Baghdasaryan
2025-10-30  8:25     ` Lorenzo Stoakes

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6c273611-e815-4a4a-822d-f6e55cec3810@infradead.org \
    --to=rdunlap@infradead.org \
    --cc=Liam.Howlett@oracle.com \
    --cc=akpm@linux-foundation.org \
    --cc=avagin@gmail.com \
    --cc=corbet@lwn.net \
    --cc=david@redhat.com \
    --cc=jannh@google.com \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-kselftest@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-trace-kernel@vger.kernel.org \
    --cc=lorenzo.stoakes@oracle.com \
    --cc=mathieu.desnoyers@efficios.com \
    --cc=mhiramat@kernel.org \
    --cc=mhocko@suse.com \
    --cc=pfalcato@suse.de \
    --cc=rostedt@goodmis.org \
    --cc=rppt@kernel.org \
    --cc=surenb@google.com \
    --cc=vbabka@suse.cz \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).