From: Willy Tarreau <w@1wt.eu>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Dmitry Vyukov <dvyukov@google.com>, Jan Kara <jack@suse.cz>,
Al Viro <viro@zeniv.linux.org.uk>,
Ben Hutchings <ben@decadent.org.uk>, Willy Tarreau <w@1wt.eu>
Subject: [PATCH 2.6.32 16/42] vfs: Avoid softlockups with sendfile(2)
Date: Sat, 23 Jan 2016 15:12:37 +0100 [thread overview]
Message-ID: <20160123141222.678312260@1wt.eu> (raw)
In-Reply-To: <aa387f55227cb730b41e3d621bf460ff@local>
2.6.32-longterm review patch. If anyone has any objections, please let me know.
------------------
From: Jan Kara <jack@suse.cz>
commit c2489e07c0a71a56fb2c84bc0ee66cddfca7d068 upstream.
The following test program from Dmitry can cause softlockups or RCU
stalls as it copies 1GB from tmpfs into eventfd and we don't have any
scheduling point at that path in sendfile(2) implementation:
int r1 = eventfd(0, 0);
int r2 = memfd_create("", 0);
unsigned long n = 1<<30;
fallocate(r2, 0, 0, n);
sendfile(r1, r2, 0, n);
Add cond_resched() into __splice_from_pipe() to fix the problem.
CC: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
(cherry picked from commit 47ae562efbd0fd8440959304915291865b945c67)
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
fs/splice.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/fs/splice.c b/fs/splice.c
index 5c006c8b..9618feb 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -882,6 +882,7 @@ ssize_t __splice_from_pipe(struct pipe_inode_info *pipe, struct splice_desc *sd,
splice_from_pipe_begin(sd);
do {
+ cond_resched();
ret = splice_from_pipe_next(pipe, sd);
if (ret > 0)
ret = splice_from_pipe_feed(pipe, sd, actor);
--
1.7.12.2.21.g234cd45.dirty
next prev parent reply other threads:[~2016-01-23 14:47 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <aa387f55227cb730b41e3d621bf460ff@local>
2016-01-23 14:12 ` [PATCH 2.6.32 01/42] ip6mr: call del_timer_sync() in ip6mr_free_table() Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 02/42] isdn_ppp: Add checks for allocation failure in isdn_ppp_open() Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 04/42] RDS: fix race condition when sending a message on unbound socket Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 05/42] unix: avoid use-after-free in ep_remove_wait_queue Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 06/42] ext4: Fix null dereference in ext4_fill_super() Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 07/42] Revert "net: add length argument to skb_copy_and_csum_datagram_iovec" Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 08/42] udp: properly support MSG_PEEK with truncated buffers Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 09/42] KEYS: Fix race between read and revoke Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 11/42] net: fix warnings in make htmldocs by moving macro definition out of field declaration Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 12/42] bluetooth: Validate socket address length in sco_sock_bind() Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 13/42] sctp: translate host order to network order when setting a hmacid Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 14/42] fuse: break infinite loop in fuse_fill_write_pages() Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 15/42] fix sysvfs symlinks Willy Tarreau
2016-01-23 14:12 ` Willy Tarreau [this message]
2016-01-23 14:12 ` [PATCH 2.6.32 17/42] ext4: Fix handling of extended tv_sec Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 18/42] nfs: if we have no valid attrs, then dont declare the attribute cache valid Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 19/42] wan/x25: Fix use-after-free in x25_asy_open_tty() Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 20/42] ipv4: igmp: Allow removing groups from a removed interface Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 21/42] sched/core: Remove false-positive warning from wake_up_process() Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 22/42] ipmi: move timer init to before irq is setup Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 23/42] tcp: initialize tp->copied_seq in case of cross SYN connection Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 24/42] net, scm: fix PaX detected msg_controllen overflow in scm_detach_fds Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 25/42] sctp: update the netstamp_needed counter when copying sockets Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 26/42] af_unix: fix a fatal race with bit fields Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 27/42] rfkill: copy the name into the rfkill struct Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 28/42] ses: Fix problems with simple enclosures Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 29/42] ses: fix additional element traversal bug Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 30/42] tty: Fix GPF in flush_to_ldisc() Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 31/42] mISDN: fix a loop count Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 32/42] ser_gigaset: fix deallocation of platform device structure Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 33/42] spi: fix parent-device reference leak Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 34/42] s390/dis: Fix handling of format specifiers Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 35/42] USB: ipaq.c: fix a timeout loop Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 36/42] USB: fix invalid memory access in hub_activate() Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 37/42] MIPS: Fix restart of indirect syscalls Willy Tarreau
2016-01-23 14:12 ` [PATCH 2.6.32 38/42] parisc: Fix syscall restarts Willy Tarreau
2016-01-23 14:13 ` [PATCH 2.6.32 39/42] ipv6/addrlabel: fix ip6addrlbl_get() Willy Tarreau
2016-01-23 14:13 ` [PATCH 2.6.32 40/42] mm/memory_hotplug.c: check for missing sections in test_pages_in_a_zone() Willy Tarreau
2016-01-23 18:13 ` Ben Hutchings
2016-01-23 18:29 ` Willy Tarreau
2016-01-23 19:05 ` Willy Tarreau
2016-01-23 14:13 ` [PATCH 2.6.32 41/42] KVM: x86: Reload pit counters for all channels when restoring state Willy Tarreau
2016-01-23 14:13 ` [PATCH 2.6.32 42/42] kvm: x86: only channel 0 of the i8254 is linked to the HPET Willy Tarreau
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