From: <rcampbell@nvidia.com>
To: <linux-mm@kvack.org>
Cc: <linux-kernel@vger.kernel.org>,
Ralph Campbell <rcampbell@nvidia.com>,
John Hubbard <jhubbard@nvidia.com>,
Ira Weiny <ira.weiny@intel.com>,
Dan Williams <dan.j.williams@intel.com>,
Arnd Bergmann <arnd@arndb.de>,
Balbir Singh <bsingharora@gmail.com>,
Dan Carpenter <dan.carpenter@oracle.com>,
Matthew Wilcox <willy@infradead.org>,
Souptick Joarder <jrdr.linux@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH 4/5] mm/hmm: hmm_vma_fault() doesn't always call hmm_range_unregister()
Date: Mon, 6 May 2019 16:29:41 -0700 [thread overview]
Message-ID: <20190506232942.12623-5-rcampbell@nvidia.com> (raw)
In-Reply-To: <20190506232942.12623-1-rcampbell@nvidia.com>
From: Ralph Campbell <rcampbell@nvidia.com>
The helper function hmm_vma_fault() calls hmm_range_register() but is
missing a call to hmm_range_unregister() in one of the error paths.
This leads to a reference count leak and ultimately a memory leak on
struct hmm.
Always call hmm_range_unregister() if hmm_range_register() succeeded.
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
---
include/linux/hmm.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index 35a429621e1e..fa0671d67269 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -559,6 +559,7 @@ static inline int hmm_vma_fault(struct hmm_range *range, bool block)
return (int)ret;
if (!hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT)) {
+ hmm_range_unregister(range);
/*
* The mmap_sem was taken by driver we release it here and
* returns -EAGAIN which correspond to mmap_sem have been
@@ -570,13 +571,13 @@ static inline int hmm_vma_fault(struct hmm_range *range, bool block)
ret = hmm_range_fault(range, block);
if (ret <= 0) {
+ hmm_range_unregister(range);
if (ret == -EBUSY || !ret) {
/* Same as above, drop mmap_sem to match old API. */
up_read(&range->vma->vm_mm->mmap_sem);
ret = -EBUSY;
} else if (ret == -EAGAIN)
ret = -EBUSY;
- hmm_range_unregister(range);
return ret;
}
return 0;
--
2.20.1
next prev parent reply other threads:[~2019-05-06 23:30 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-06 23:29 [PATCH 0/5] mm/hmm: HMM documentation updates and code fixes rcampbell
2019-05-06 23:29 ` [PATCH 1/5] mm/hmm: Update HMM documentation rcampbell
2019-06-06 14:02 ` Jason Gunthorpe
2019-06-06 18:50 ` Ralph Campbell
2019-06-06 19:32 ` Jason Gunthorpe
2019-05-06 23:29 ` [PATCH 2/5] mm/hmm: Clean up some coding style and comments rcampbell
2019-06-06 14:16 ` Jason Gunthorpe
2019-06-06 14:27 ` Jerome Glisse
2019-06-06 15:41 ` Jason Gunthorpe
2019-06-06 15:52 ` Jerome Glisse
2019-06-06 16:55 ` Joe Perches
2019-06-06 18:54 ` Jason Gunthorpe
2019-06-06 15:57 ` Jason Gunthorpe
2019-06-07 0:44 ` Ralph Campbell
2019-05-06 23:29 ` [PATCH 3/5] mm/hmm: Use mm_get_hmm() in hmm_range_register() rcampbell
2019-05-23 12:51 ` Jason Gunthorpe
2019-05-23 18:19 ` Ralph Campbell
2019-05-23 18:46 ` John Hubbard
2019-05-06 23:29 ` rcampbell [this message]
2019-05-07 13:15 ` [PATCH 4/5] mm/hmm: hmm_vma_fault() doesn't always call hmm_range_unregister() Souptick Joarder
2019-05-07 18:12 ` Ralph Campbell
2019-05-09 4:42 ` Souptick Joarder
2019-05-12 15:07 ` Jerome Glisse
2019-05-12 15:28 ` Jerome Glisse
2019-05-13 17:23 ` Ralph Campbell
2019-06-06 14:50 ` Jason Gunthorpe
2019-06-06 19:44 ` Ralph Campbell
2019-06-06 19:54 ` Jason Gunthorpe
2019-06-06 21:08 ` Ralph Campbell
2019-05-12 15:08 ` [PATCH 0/5] mm/hmm: HMM documentation updates and code fixes Jerome Glisse
2019-05-13 17:26 ` Ralph Campbell
2019-05-13 18:10 ` Jerome Glisse
2019-06-06 14:53 ` Jason Gunthorpe
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=20190506232942.12623-5-rcampbell@nvidia.com \
--to=rcampbell@nvidia.com \
--cc=akpm@linux-foundation.org \
--cc=arnd@arndb.de \
--cc=bsingharora@gmail.com \
--cc=dan.carpenter@oracle.com \
--cc=dan.j.williams@intel.com \
--cc=ira.weiny@intel.com \
--cc=jhubbard@nvidia.com \
--cc=jrdr.linux@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=willy@infradead.org \
/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).