From: Christoph Hellwig <hch@lst.de>
To: "Jérôme Glisse" <jglisse@redhat.com>,
"Jason Gunthorpe" <jgg@mellanox.com>,
"Ben Skeggs" <bskeggs@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>,
linux-mm@kvack.org, nouveau@lists.freedesktop.org,
dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: [PATCH 4/7] nouveau: unlock mmap_sem on all errors from nouveau_range_fault
Date: Wed, 24 Jul 2019 08:52:55 +0200 [thread overview]
Message-ID: <20190724065258.16603-5-hch@lst.de> (raw)
In-Reply-To: <20190724065258.16603-1-hch@lst.de>
Currently nouveau_svm_fault expects nouveau_range_fault to never unlock
mmap_sem, but the latter unlocks it for a random selection of error
codes. Fix this up by always unlocking mmap_sem for non-zero return
values in nouveau_range_fault, and only unlocking it in the caller
for successful returns.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/gpu/drm/nouveau/nouveau_svm.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c
index e3097492b4ad..a835cebb6d90 100644
--- a/drivers/gpu/drm/nouveau/nouveau_svm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_svm.c
@@ -495,8 +495,10 @@ nouveau_range_fault(struct hmm_mirror *mirror, struct hmm_range *range)
ret = hmm_range_register(range, mirror,
range->start, range->end,
PAGE_SHIFT);
- if (ret)
+ if (ret) {
+ up_read(&range->vma->vm_mm->mmap_sem);
return (int)ret;
+ }
if (!hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT)) {
up_read(&range->vma->vm_mm->mmap_sem);
@@ -505,10 +507,9 @@ nouveau_range_fault(struct hmm_mirror *mirror, struct hmm_range *range)
ret = hmm_range_fault(range, true);
if (ret <= 0) {
- if (ret == -EBUSY || !ret) {
- up_read(&range->vma->vm_mm->mmap_sem);
+ if (ret == 0)
ret = -EBUSY;
- }
+ up_read(&range->vma->vm_mm->mmap_sem);
hmm_range_unregister(range);
return ret;
}
@@ -706,8 +707,8 @@ nouveau_svm_fault(struct nvif_notify *notify)
NULL);
svmm->vmm->vmm.object.client->super = false;
mutex_unlock(&svmm->mutex);
+ up_read(&svmm->mm->mmap_sem);
}
- up_read(&svmm->mm->mmap_sem);
/* Cancel any faults in the window whose pages didn't manage
* to keep their valid bit, or stay writeable when required.
--
2.20.1
next prev parent reply other threads:[~2019-07-24 6:53 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-24 6:52 hmm_range_fault related fixes and legacy API removal v3 Christoph Hellwig
2019-07-24 6:52 ` [PATCH 1/7] mm: always return EBUSY for invalid ranges in hmm_range_{fault,snapshot} Christoph Hellwig
2019-07-24 6:52 ` [PATCH 2/7] mm: move hmm_vma_range_done and hmm_vma_fault to nouveau Christoph Hellwig
2019-07-24 6:52 ` [PATCH 3/7] nouveau: remove the block parameter to nouveau_range_fault Christoph Hellwig
2019-07-24 6:52 ` Christoph Hellwig [this message]
2019-07-24 6:52 ` [PATCH 5/7] nouveau: return -EBUSY when hmm_range_wait_until_valid fails Christoph Hellwig
2019-07-24 6:52 ` [PATCH 6/7] mm: remove the legacy hmm_pfn_* APIs Christoph Hellwig
2019-07-24 6:52 ` [PATCH 7/7] mm: comment on VM_FAULT_RETRY semantics in handle_mm_fault Christoph Hellwig
2019-07-26 0:16 ` hmm_range_fault related fixes and legacy API removal v3 Jason Gunthorpe
2019-07-26 0:55 ` Ralph Campbell
2019-07-26 4:57 ` Christoph Hellwig
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=20190724065258.16603-5-hch@lst.de \
--to=hch@lst.de \
--cc=bskeggs@redhat.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=jgg@mellanox.com \
--cc=jglisse@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=nouveau@lists.freedesktop.org \
--cc=rcampbell@nvidia.com \
/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).