diff options
| author | Johan Hovold <johan@kernel.org> | 2021-03-22 12:12:49 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-23 12:37:46 +0100 |
| commit | 8219ab4c9a09bc746614daaf5240fec82e7fe0e7 (patch) | |
| tree | e47ad3192b4fedf8900b16c2dd0f88f584da0129 | |
| parent | 0b9828763aeafa5e527b9d98b8789bdb34937fbc (diff) | |
| download | linux-8219ab4c9a09bc746614daaf5240fec82e7fe0e7.tar.bz2 | |
USB: ehci: drop workaround for forced irq threading
Force-threaded interrupt handlers used to run with interrupts enabled,
something which could lead to deadlocks in case a threaded handler
shared a lock with code running in hard interrupt context (e.g. timer
callbacks) and did not explicitly disable interrupts.
Since commit 81e2073c175b ("genirq: Disable interrupts for force
threaded handlers") interrupt handlers always run with interrupts
disabled on non-RT so that drivers no longer need to do handle forced
threading ("threadirqs").
Drop the now obsolete workaround added by commit a1227f3c1030 ("usb:
ehci: fix deadlock when threadirqs option is used").
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210322111249.32141-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/host/ehci-hcd.c | 13 |
1 files changed, 3 insertions, 10 deletions
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index 2237d22d292a..94b5e64ae9a2 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -705,15 +705,8 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd) struct ehci_hcd *ehci = hcd_to_ehci (hcd); u32 status, masked_status, pcd_status = 0, cmd; int bh; - unsigned long flags; - /* - * For threadirqs option we use spin_lock_irqsave() variant to prevent - * deadlock with ehci hrtimer callback, because hrtimer callbacks run - * in interrupt context even when threadirqs is specified. We can go - * back to spin_lock() variant when hrtimer callbacks become threaded. - */ - spin_lock_irqsave(&ehci->lock, flags); + spin_lock(&ehci->lock); status = ehci_readl(ehci, &ehci->regs->status); @@ -731,7 +724,7 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd) /* Shared IRQ? */ if (!masked_status || unlikely(ehci->rh_state == EHCI_RH_HALTED)) { - spin_unlock_irqrestore(&ehci->lock, flags); + spin_unlock(&ehci->lock); return IRQ_NONE; } @@ -842,7 +835,7 @@ dead: if (bh) ehci_work (ehci); - spin_unlock_irqrestore(&ehci->lock, flags); + spin_unlock(&ehci->lock); if (pcd_status) usb_hcd_poll_rh_status(hcd); return IRQ_HANDLED; |