* [PATCH 0/2] Two minor 5.11 io_uring fixes
@ 2020-12-17 15:21 Jens Axboe
2020-12-17 15:21 ` [PATCH 1/2] io_uring: break links on shutdown failure Jens Axboe
2020-12-17 15:21 ` [PATCH 2/2] io_uring: hold mmap_sem for mm->locked_vm manipulation Jens Axboe
0 siblings, 2 replies; 3+ messages in thread
From: Jens Axboe @ 2020-12-17 15:21 UTC (permalink / raw)
To: io-uring
Hi,
1) Make sure we break links if a shutdown command fails
2) Play it safe and grab mmap_sem when modifying mm->locked_vm
--
Jens Axboe
^ permalink raw reply [flat|nested] 3+ messages in thread
* [PATCH 1/2] io_uring: break links on shutdown failure
2020-12-17 15:21 [PATCH 0/2] Two minor 5.11 io_uring fixes Jens Axboe
@ 2020-12-17 15:21 ` Jens Axboe
2020-12-17 15:21 ` [PATCH 2/2] io_uring: hold mmap_sem for mm->locked_vm manipulation Jens Axboe
1 sibling, 0 replies; 3+ messages in thread
From: Jens Axboe @ 2020-12-17 15:21 UTC (permalink / raw)
To: io-uring; +Cc: Jens Axboe
Ensure that the return value of __sys_shutdown_sock() is used to
potentially break links to the request, if we fail.
Fixes: 36f4fa6886a8 ("io_uring: add support for shutdown(2)")
Signed-off-by: Jens Axboe <[email protected]>
---
fs/io_uring.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 6f9392c35eef..6a4560c9ed9a 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3784,6 +3784,8 @@ static int io_shutdown(struct io_kiocb *req, bool force_nonblock)
return -ENOTSOCK;
ret = __sys_shutdown_sock(sock, req->shutdown.how);
+ if (ret < 0)
+ req_set_fail_links(req);
io_req_complete(req, ret);
return 0;
#else
--
2.29.2
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH 2/2] io_uring: hold mmap_sem for mm->locked_vm manipulation
2020-12-17 15:21 [PATCH 0/2] Two minor 5.11 io_uring fixes Jens Axboe
2020-12-17 15:21 ` [PATCH 1/2] io_uring: break links on shutdown failure Jens Axboe
@ 2020-12-17 15:21 ` Jens Axboe
1 sibling, 0 replies; 3+ messages in thread
From: Jens Axboe @ 2020-12-17 15:21 UTC (permalink / raw)
To: io-uring; +Cc: Jens Axboe
The kernel doesn't seem to have clear rules around this, but various
spots are using the mmap_sem to serialize access to modifying the
locked_vm count. Play it safe and lock the mm for write when accounting
or unaccounting locked memory.
Signed-off-by: Jens Axboe <[email protected]>
---
fs/io_uring.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 6a4560c9ed9a..2d07d35e7262 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -8157,10 +8157,13 @@ static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages,
__io_unaccount_mem(ctx->user, nr_pages);
if (ctx->mm_account) {
- if (acct == ACCT_LOCKED)
+ if (acct == ACCT_LOCKED) {
+ mmap_write_lock(ctx->mm_account);
ctx->mm_account->locked_vm -= nr_pages;
- else if (acct == ACCT_PINNED)
+ mmap_write_unlock(ctx->mm_account);
+ }else if (acct == ACCT_PINNED) {
atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
+ }
}
}
@@ -8176,10 +8179,13 @@ static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages,
}
if (ctx->mm_account) {
- if (acct == ACCT_LOCKED)
+ if (acct == ACCT_LOCKED) {
+ mmap_write_lock(ctx->mm_account);
ctx->mm_account->locked_vm += nr_pages;
- else if (acct == ACCT_PINNED)
+ mmap_write_unlock(ctx->mm_account);
+ } else if (acct == ACCT_PINNED) {
atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
+ }
}
return 0;
--
2.29.2
^ permalink raw reply related [flat|nested] 3+ messages in thread
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2020-12-17 15:21 [PATCH 0/2] Two minor 5.11 io_uring fixes Jens Axboe
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