Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1604960

[PATCH 4.10 61/63] locking/rwsem: Fix down_write_killable() for CONFIG_RWSEM_GENERIC_SPINLOCK=y

Show all headers | View raw

4.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Niklas Cassel <niklas.cassel@axis.com>

commit 17fcbd590d0c3e35bd9646e2215f86586378bc42 upstream.

We hang if SIGKILL has been sent, but the task is stuck in down_read()
(after do_exit()), even though no task is doing down_write() on the
rwsem in question:

  INFO: task libupnp:21868 blocked for more than 120 seconds.
  libupnp         D    0 21868      1 0x08100008
  ...
  Call Trace:
  __schedule()
  schedule()
  __down_read()
  do_exit()
  do_group_exit()
  __wake_up_parent()

This bug has already been fixed for CONFIG_RWSEM_XCHGADD_ALGORITHM=y in
the following commit:

 04cafed7fc19 ("locking/rwsem: Fix down_write_killable()")

... however, this bug also exists for CONFIG_RWSEM_GENERIC_SPINLOCK=y.

Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <mhocko@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Niklas Cassel <niklass@axis.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: d47996082f52 ("locking/rwsem: Introduce basis for down_write_killable()")
Link: http://lkml.kernel.org/r/1487981873-12649-1-git-send-email-niklass@axis.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 kernel/locking/rwsem-spinlock.c |   15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

--- a/kernel/locking/rwsem-spinlock.c
+++ b/kernel/locking/rwsem-spinlock.c
@@ -216,10 +216,8 @@ int __sched __down_write_common(struct r
 		 */
 		if (sem->count == 0)
 			break;
-		if (signal_pending_state(state, current)) {
-			ret = -EINTR;
-			goto out;
-		}
+		if (signal_pending_state(state, current))
+			goto out_nolock;
 		set_task_state(tsk, state);
 		raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
 		schedule();
@@ -227,12 +225,19 @@ int __sched __down_write_common(struct r
 	}
 	/* got the lock */
 	sem->count = -1;
-out:
 	list_del(&waiter.list);
 
 	raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
 
 	return ret;
+
+out_nolock:
+	list_del(&waiter.list);
+	if (!list_empty(&sem->wait_list))
+		__rwsem_do_wake(sem, 1);
+	raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
+
+	return -EINTR;
 }
 
 void __sched __down_write(struct rw_semaphore *sem)

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 4.10 00/63] 4.10.5-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 31/63] net: fix socket refcounting in skb_complete_tx_timestamp() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 33/63] dccp: fix use-after-free in dccp_feat_activate_values Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 32/63] net/sched: act_skbmod: remove unneeded rcu_read_unlock in tcf_skbmod_dump Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 08/63] vti6: return GRE_KEY for vti6 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 07/63] vxlan: correctly validate VXLAN ID against VXLAN_N_VID Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 13/63] net sched actions: decrement module reference count after table flush. Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 06/63] sctp: deny peeloff operation on asocs with threads sleeping on it Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 35/63] vrf: Fix use-after-free in vrf_xmit Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 16/63] geneve: lock RCU on TX path Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 21/63] net: net_enable_timestamp() can be called from irq contexts Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 40/63] mpls: Send route delete notifications when router module is unloaded Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 36/63] net/tunnel: set inner protocol in network gro hooks Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 29/63] tcp: fix various issues for sockets morphing to listen state Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 27/63] bonding: use ETH_MAX_MTU as max mtu Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:10 +0100
  [PATCH 4.10 17/63] mlxsw: spectrum_router: Avoid potential packets loss Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 59/63] futex: Fix potential use-after-free in FUTEX_REQUEUE_PI Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 38/63] amd-xgbe: Enable IRQs only if napi_complete_done() is true Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 60/63] futex: Add missing error handling to FUTEX_REQUEUE_PI Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 22/63] ipv6: orphan skbs in reassembly unit Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 56/63] x86/kasan: Fix boot with KASAN=y and PROFILE_ANNOTATED_BRANCHES=y Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 49/63] arm64: KVM: VHE: Clear HCR_TGE when invalidating guest TLBs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 05/63] net/mlx5e: Fix wrong CQE decompression Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 09/63] vxlan: dont allow overwrite of config src addr Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 43/63] ipv6: avoid write to a possibly cloned skb Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 61/63] locking/rwsem: Fix down_write_killable() for CONFIG_RWSEM_GENERIC_SPINLOCK=y Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 41/63] mpls: Do not decrement alive counter for unregister events Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 15/63] vxlan: lock RCU on TX path Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 03/63] net/mlx5e: Fix broken CQE compression initialization Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 37/63] uapi: fix linux/packet_diag.h userspace compilation error Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 50/63] irqchip/gicv3-its: Add workaround for QDF2400 ITS erratum 0065 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 26/63] amd-xgbe: Dont overwrite SFP PHY mod_absent settings Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 12/63] sctp: set sin_port for addr param when checking duplicate address Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 23/63] dccp: Unlock sock before calling sk_free() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 04/63] net/mlx5e: Update MPWQE stride size when modifying CQE compress state Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 10/63] ipv4: add missing initialization for flowi4_uid Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 62/63] crypto: powerpc - Fix initialisation of crc32c context Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  [PATCH 4.10 25/63] amd-xgbe: Be sure to set MDIO modes on device (re)start Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-20 19:20 +0100
  Re: [PATCH 4.10 00/63] 4.10.5-stable review Shuah Khan <shuahkh@osg.samsung.com> - 2017-03-21 01:20 +0100
    Re: [PATCH 4.10 00/63] 4.10.5-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-21 05:40 +0100
  Re: [PATCH 4.10 00/63] 4.10.5-stable review Guenter Roeck <linux@roeck-us.net> - 2017-03-21 03:20 +0100
    Re: [PATCH 4.10 00/63] 4.10.5-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-03-21 05:50 +0100

csiph-web