This is a note to let you know that I've just added the patch titled USB: musb: fix late external abort on suspend to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From 0c3aae9bd59978fb8c3557d7883380bef0f2cfa1 Mon Sep 17 00:00:00 2001 From: Johan Hovold <johan@xxxxxxxxxx> Date: Mon, 9 Oct 2017 22:46:08 -0500 Subject: USB: musb: fix late external abort on suspend The musb delayed irq work was never flushed on suspend, something which since 4.9 can lead to an external abort if the work is scheduled after the grandparent's clock has been disabled: PM: Suspending system (mem) PM: suspend of devices complete after 125.224 msecs PM: suspend devices took 0.132 seconds PM: late suspend of devices complete after 7.423 msecs PM: noirq suspend of devices complete after 7.083 msecs suspend debug: Waiting for 5 second(s). Unhandled fault: external abort on non-linefetch (0x1008) at 0xd0262c60 ... [<c054880c>] (musb_default_readb) from [<c0547b5c>] (musb_irq_work+0x48/0x220) [<c0547b5c>] (musb_irq_work) from [<c014f8a4>] (process_one_work+0x1f4/0x758) [<c014f8a4>] (process_one_work) from [<c014fe5c>] (worker_thread+0x54/0x514) [<c014fe5c>] (worker_thread) from [<c015704c>] (kthread+0x128/0x158) [<c015704c>] (kthread) from [<c0109330>] (ret_from_fork+0x14/0x24) Commit 2bff3916fda9 ("usb: musb: Fix PM for hub disconnect") started scheduling musb_irq_work with a delay of up to a second and with retries thereby making this easy to trigger, for example, by suspending shortly after a disconnect. Note that we set a flag to prevent the irq work from rescheduling itself during suspend and instead process a disconnect immediately. This takes care of the case where we are disconnected shortly before suspending. However, when in host mode, a disconnect while suspended will still go unnoticed and thus prevent the controller from runtime suspending upon resume as the session bit is always set. This will need to be addressed separately. Fixes: 550a7375fe72 ("USB: Add MUSB and TUSB support") Fixes: 467d5c980709 ("usb: musb: Implement session bit based runtime PM for musb-core") Fixes: 2bff3916fda9 ("usb: musb: Fix PM for hub disconnect") Cc: stable <stable@xxxxxxxxxxxxxxx> # 4.9 Cc: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> Cc: Tony Lindgren <tony@xxxxxxxxxxx> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> Tested-by: Tony Lindgren <tony@xxxxxxxxxxx> Signed-off-by: Bin Liu <b-liu@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/musb/musb_core.c | 11 +++++++++-- drivers/usb/musb/musb_core.h | 2 ++ 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c index 07b8c7152e3d..1ced3af75b05 100644 --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -1861,7 +1861,7 @@ static void musb_pm_runtime_check_session(struct musb *musb) MUSB_DEVCTL_HR; switch (devctl & ~s) { case MUSB_QUIRK_B_INVALID_VBUS_91: - if (musb->quirk_retries) { + if (musb->quirk_retries && !musb->flush_irq_work) { musb_dbg(musb, "Poll devctl on invalid vbus, assume no session"); schedule_delayed_work(&musb->irq_work, @@ -1871,7 +1871,7 @@ static void musb_pm_runtime_check_session(struct musb *musb) } /* fall through */ case MUSB_QUIRK_A_DISCONNECT_19: - if (musb->quirk_retries) { + if (musb->quirk_retries && !musb->flush_irq_work) { musb_dbg(musb, "Poll devctl on possible host mode disconnect"); schedule_delayed_work(&musb->irq_work, @@ -2681,8 +2681,15 @@ static int musb_suspend(struct device *dev) musb_platform_disable(musb); musb_disable_interrupts(musb); + + musb->flush_irq_work = true; + while (flush_delayed_work(&musb->irq_work)) + ; + musb->flush_irq_work = false; + if (!(musb->io.quirks & MUSB_PRESERVE_SESSION)) musb_writeb(musb->mregs, MUSB_DEVCTL, 0); + WARN_ON(!list_empty(&musb->pending_list)); spin_lock_irqsave(&musb->lock, flags); diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h index c748f4ac1154..20f4614178d9 100644 --- a/drivers/usb/musb/musb_core.h +++ b/drivers/usb/musb/musb_core.h @@ -428,6 +428,8 @@ struct musb { unsigned test_mode:1; unsigned softconnect:1; + unsigned flush_irq_work:1; + u8 address; u8 test_mode_nr; u16 ackpend; /* ep0 */ -- 2.14.2