From: Minchan Kim <minchan@kernel.org>
To: Suren Baghdasaryan <surenb@google.com>
Cc: sumit.semwal@linaro.org, akpm@linux-foundation.org,
hch@infradead.org, lmark@codeaurora.org, labbott@redhat.com,
Brian.Starkey@arm.com, john.stultz@linaro.org,
christian.koenig@amd.com, cgoldswo@codeaurora.org,
orjan.eide@arm.com, robin.murphy@arm.com, jajones@nvidia.com,
hridya@google.com, sspatil@google.com,
linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org,
linaro-mm-sig@lists.linaro.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org, kernel-team@android.com
Subject: Re: [PATCH 1/2] mm: replace BUG_ON in vm_insert_page with a return of an error
Date: Tue, 2 Feb 2021 17:31:03 -0800 [thread overview]
Message-ID: <YBn81xAeCqHgudYb@google.com> (raw)
In-Reply-To: <20210203003134.2422308-1-surenb@google.com>
On Tue, Feb 02, 2021 at 04:31:33PM -0800, Suren Baghdasaryan wrote:
> Replace BUG_ON(vma->vm_flags & VM_PFNMAP) in vm_insert_page with
> WARN_ON_ONCE and returning an error. This is to ensure users of the
> vm_insert_page that set VM_PFNMAP are notified of the wrong flag usage
> and get an indication of an error without panicing the kernel.
> This will help identifying drivers that need to clear VM_PFNMAP before
> using dmabuf system heap which is moving to use vm_insert_page.
>
> Suggested-by: Christoph Hellwig <hch@infradead.org>
> Signed-off-by: Suren Baghdasaryan <surenb@google.com>
> ---
> mm/memory.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/mm/memory.c b/mm/memory.c
> index feff48e1465a..e503c9801cd9 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -1827,7 +1827,8 @@ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr,
> return -EINVAL;
> if (!(vma->vm_flags & VM_MIXEDMAP)) {
> BUG_ON(mmap_read_trylock(vma->vm_mm));
Better to replace above BUG_ON with WARN_ON_ONCE, too?
next prev parent reply other threads:[~2021-02-03 1:32 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-03 0:31 [PATCH 1/2] mm: replace BUG_ON in vm_insert_page with a return of an error Suren Baghdasaryan
2021-02-03 0:31 ` [PATCH v2 2/2] dma-buf: heaps: Map system heap pages as managed by linux vm Suren Baghdasaryan
2021-02-03 1:39 ` Minchan Kim
2021-02-03 2:02 ` Suren Baghdasaryan
2021-02-03 8:05 ` Christian König
2021-02-03 19:53 ` Suren Baghdasaryan
2021-02-03 2:07 ` John Stultz
2021-02-03 2:13 ` Suren Baghdasaryan
2021-02-03 1:27 ` [PATCH 1/2] mm: replace BUG_ON in vm_insert_page with a return of an error Miaohe Lin
2021-02-03 1:31 ` Minchan Kim [this message]
2021-02-03 1:55 ` Suren Baghdasaryan
2021-02-03 1:55 ` Matthew Wilcox
2021-02-03 2:26 ` Suren Baghdasaryan
2021-02-03 8:52 ` [Linaro-mm-sig] " Daniel Vetter
2021-02-03 20:20 ` Suren Baghdasaryan
2021-02-03 20:29 ` Daniel Vetter
2021-02-03 21:25 ` Daniel Vetter
2021-02-03 21:41 ` Suren Baghdasaryan
2021-02-04 8:16 ` Christian König
2021-02-04 15:22 ` Daniel Vetter
2021-02-04 15:54 ` Alex Deucher
2021-02-05 3:39 ` Suren Baghdasaryan
2021-02-04 7:53 ` Christian König
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