| Message ID | Z1n9v7Z6iNJ-wKmq@slm.duckdns.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [sched_ext/for-6.13-fixes] sched_ext: Fix invalid irq restore in scx_ops_bypass() | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Wed, Dec 11, 2024 at 11:01:51AM -1000, Tejun Heo wrote: > While adding outer irqsave/restore locking, 0e7ffff1b811 ("scx: Fix raciness > in scx_ops_bypass()") forgot to convert an inner rq_unlock_irqrestore() to > rq_unlock() which could re-enable IRQ prematurely leading to the following > warning: > > raw_local_irq_restore() called with IRQs enabled > WARNING: CPU: 1 PID: 96 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x30/0x40 > ... > Sched_ext: create_dsq (enabling) > pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : warn_bogus_irq_restore+0x30/0x40 > lr : warn_bogus_irq_restore+0x30/0x40 > ... > Call trace: > warn_bogus_irq_restore+0x30/0x40 (P) > warn_bogus_irq_restore+0x30/0x40 (L) > scx_ops_bypass+0x224/0x3b8 > scx_ops_enable.isra.0+0x2c8/0xaa8 > bpf_scx_reg+0x18/0x30 > ... > irq event stamp: 33739 > hardirqs last enabled at (33739): [<ffff8000800b699c>] scx_ops_bypass+0x174/0x3b8 > hardirqs last disabled at (33738): [<ffff800080d48ad4>] _raw_spin_lock_irqsave+0xb4/0xd8 > > Drop the stray _irqrestore(). > > Signed-off-by: Tejun Heo <tj@kernel.org> > Reported-by: Ihor Solodrai <ihor.solodrai@pm.me> > Link: http://lkml.kernel.org/r/qC39k3UsonrBYD_SmuxHnZIQLsuuccoCrkiqb_BT7DvH945A1_LZwE4g-5Pu9FcCtqZt4lY1HhIPi0homRuNWxkgo1rgP3bkxa0donw8kV4=@pm.me > Fixes: 0e7ffff1b811 ("scx: Fix raciness in scx_ops_bypass()") > Cc: stable@vger.kernel.org # v6.12 Applying to sched_ext/for-6.13-fixes. Thanks.
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 7fff1d045477..98519e6d0dcd 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -4763,7 +4763,7 @@ static void scx_ops_bypass(bool bypass) * sees scx_rq_bypassing() before moving tasks to SCX. */ if (!scx_enabled()) { - rq_unlock_irqrestore(rq, &rf); + rq_unlock(rq, &rf); continue; }
While adding outer irqsave/restore locking, 0e7ffff1b811 ("scx: Fix raciness in scx_ops_bypass()") forgot to convert an inner rq_unlock_irqrestore() to rq_unlock() which could re-enable IRQ prematurely leading to the following warning: raw_local_irq_restore() called with IRQs enabled WARNING: CPU: 1 PID: 96 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x30/0x40 ... Sched_ext: create_dsq (enabling) pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : warn_bogus_irq_restore+0x30/0x40 lr : warn_bogus_irq_restore+0x30/0x40 ... Call trace: warn_bogus_irq_restore+0x30/0x40 (P) warn_bogus_irq_restore+0x30/0x40 (L) scx_ops_bypass+0x224/0x3b8 scx_ops_enable.isra.0+0x2c8/0xaa8 bpf_scx_reg+0x18/0x30 ... irq event stamp: 33739 hardirqs last enabled at (33739): [<ffff8000800b699c>] scx_ops_bypass+0x174/0x3b8 hardirqs last disabled at (33738): [<ffff800080d48ad4>] _raw_spin_lock_irqsave+0xb4/0xd8 Drop the stray _irqrestore(). Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Ihor Solodrai <ihor.solodrai@pm.me> Link: http://lkml.kernel.org/r/qC39k3UsonrBYD_SmuxHnZIQLsuuccoCrkiqb_BT7DvH945A1_LZwE4g-5Pu9FcCtqZt4lY1HhIPi0homRuNWxkgo1rgP3bkxa0donw8kV4=@pm.me Fixes: 0e7ffff1b811 ("scx: Fix raciness in scx_ops_bypass()") Cc: stable@vger.kernel.org # v6.12 --- kernel/sched/ext.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)