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Diffstat (limited to 'target/linux/brcm2708/patches-4.19/950-0365-dwc_otg-fix-locking-around-dequeueing-and-killing-UR.patch')
-rw-r--r--target/linux/brcm2708/patches-4.19/950-0365-dwc_otg-fix-locking-around-dequeueing-and-killing-UR.patch63
1 files changed, 63 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.19/950-0365-dwc_otg-fix-locking-around-dequeueing-and-killing-UR.patch b/target/linux/brcm2708/patches-4.19/950-0365-dwc_otg-fix-locking-around-dequeueing-and-killing-UR.patch
new file mode 100644
index 0000000000..53e2c98ce5
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.19/950-0365-dwc_otg-fix-locking-around-dequeueing-and-killing-UR.patch
@@ -0,0 +1,63 @@
+From ea7ff2070d564858c445cfdbd883ea00927c0ada Mon Sep 17 00:00:00 2001
+From: P33M <p33m@github.com>
+Date: Tue, 9 Apr 2019 16:40:48 +0100
+Subject: [PATCH] dwc_otg: fix locking around dequeueing and killing
+ URBs
+
+kill_urbs_in_qh_list() is practically only ever called with the fiq lock
+already held, so don't spinlock twice in the case where we need to cancel
+an isochronous transfer.
+
+Also fix up a case where the global interrupt register could be read with
+the fiq lock not held.
+
+Fixes the deadlock seen in https://github.com/raspberrypi/linux/issues/2907
+---
+ drivers/usb/host/dwc_otg/dwc_otg_cil_intr.c | 9 +++++++--
+ drivers/usb/host/dwc_otg/dwc_otg_hcd.c | 4 ----
+ 2 files changed, 7 insertions(+), 6 deletions(-)
+
+--- a/drivers/usb/host/dwc_otg/dwc_otg_cil_intr.c
++++ b/drivers/usb/host/dwc_otg/dwc_otg_cil_intr.c
+@@ -1344,16 +1344,21 @@ static inline uint32_t dwc_otg_read_comm
+ */
+ gintmsk_common.b.portintr = 1;
+ }
+- gintsts.d32 = DWC_READ_REG32(&core_if->core_global_regs->gintsts);
+- gintmsk.d32 = DWC_READ_REG32(&core_if->core_global_regs->gintmsk);
+ if(fiq_enable) {
+ local_fiq_disable();
++ fiq_fsm_spin_lock(&hcd->fiq_state->lock);
++ gintsts.d32 = DWC_READ_REG32(&core_if->core_global_regs->gintsts);
++ gintmsk.d32 = DWC_READ_REG32(&core_if->core_global_regs->gintmsk);
+ /* Pull in the interrupts that the FIQ has masked */
+ gintmsk.d32 |= ~(hcd->fiq_state->gintmsk_saved.d32);
+ gintmsk.d32 |= gintmsk_common.d32;
+ /* for the upstairs function to reenable - have to read it here in case FIQ triggers again */
+ reenable_gintmsk->d32 = gintmsk.d32;
++ fiq_fsm_spin_unlock(&hcd->fiq_state->lock);
+ local_fiq_enable();
++ } else {
++ gintsts.d32 = DWC_READ_REG32(&core_if->core_global_regs->gintsts);
++ gintmsk.d32 = DWC_READ_REG32(&core_if->core_global_regs->gintmsk);
+ }
+
+ gahbcfg.d32 = DWC_READ_REG32(&core_if->core_global_regs->gahbcfg);
+--- a/drivers/usb/host/dwc_otg/dwc_otg_hcd.c
++++ b/drivers/usb/host/dwc_otg/dwc_otg_hcd.c
+@@ -195,15 +195,11 @@ static void kill_urbs_in_qh_list(dwc_otg
+ * but not yet been through the IRQ handler.
+ */
+ if (fiq_fsm_enable && (hcd->fiq_state->channel[qh->channel->hc_num].fsm != FIQ_PASSTHROUGH)) {
+- local_fiq_disable();
+- fiq_fsm_spin_lock(&hcd->fiq_state->lock);
+ qh->channel->halt_status = DWC_OTG_HC_XFER_URB_DEQUEUE;
+ qh->channel->halt_pending = 1;
+ if (hcd->fiq_state->channel[n].fsm == FIQ_HS_ISOC_TURBO ||
+ hcd->fiq_state->channel[n].fsm == FIQ_HS_ISOC_SLEEPING)
+ hcd->fiq_state->channel[n].fsm = FIQ_HS_ISOC_ABORTED;
+- fiq_fsm_spin_unlock(&hcd->fiq_state->lock);
+- local_fiq_enable();
+ } else {
+ dwc_otg_hc_halt(hcd->core_if, qh->channel,
+ DWC_OTG_HC_XFER_URB_DEQUEUE);