Messages in this thread | | | Date | Tue, 30 Apr 2024 10:10:35 +0200 | From | Gerd Hoffmann <> | Subject | Re: [PATCH v3] usb: ohci: Prevent missed ohci interrupts |
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On Mon, Apr 29, 2024 at 08:40:10AM GMT, Guenter Roeck wrote: > Testing ohci functionality with qemu's pci-ohci emulation often results > in ohci interface stalls, resulting in hung task timeouts. > > The problem is caused by lost interrupts between the emulation and the > Linux kernel code. Additional interrupts raised while the ohci interrupt > handler in Linux is running and before the handler clears the interrupt > status are not handled. The fix for a similar problem in ehci suggests > that the problem is likely caused by edge-triggered MSI interrupts. See > commit 0b60557230ad ("usb: ehci: Prevent missed ehci interrupts with > edge-triggered MSI") for details. > > Ensure that the ohci interrupt code handles all pending interrupts before > returning to solve the problem. > > Cc: Gerd Hoffmann <kraxel@redhat.com> > Cc: David Laight <David.Laight@aculab.com> > Cc: stable@vger.kernel.org > Fixes: 306c54d0edb6 ("usb: hcd: Try MSI interrupts on PCI devices") > Signed-off-by: Guenter Roeck <linux@roeck-us.net> > --- > v3: Check if any interrupts are pending before reading intrenable > Add 'Cc: stable@vger.kernel.org' > v2: Only repeat if the interface is still active
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
take care, Gerd
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