50 lines
2.0 KiB
Diff
50 lines
2.0 KiB
Diff
From 3254821606ce89fd2a2d2bbd115d6b4e61f7cd9b Mon Sep 17 00:00:00 2001
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Message-Id: <3254821606ce89fd2a2d2bbd115d6b4e61f7cd9b.1601675151.git.zanussi@kernel.org>
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In-Reply-To: <5b5a156f9808b1acf1205606e03da117214549ea.1601675151.git.zanussi@kernel.org>
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References: <5b5a156f9808b1acf1205606e03da117214549ea.1601675151.git.zanussi@kernel.org>
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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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Date: Fri, 8 Nov 2013 17:34:54 +0100
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Subject: [PATCH 035/333] usb: do no disable interrupts in giveback
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Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.148-rt64.tar.xz
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Since commit 94dfd7ed ("USB: HCD: support giveback of URB in tasklet
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context") the USB code disables interrupts before invoking the complete
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callback.
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This should not be required the HCD completes the URBs either in hard-irq
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context or in BH context. Lockdep may report false positives if one has two
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HCDs (one completes in IRQ and the other in BH context) and is using the same
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USB driver (device) with both HCDs. This is safe since the same URBs are never
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mixed with those two HCDs.
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Longeterm we should force all HCDs to complete in the same context.
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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drivers/usb/core/hcd.c | 3 ---
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1 file changed, 3 deletions(-)
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diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
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index b82a7d787add..2f3015356124 100644
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--- a/drivers/usb/core/hcd.c
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+++ b/drivers/usb/core/hcd.c
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@@ -1738,7 +1738,6 @@ static void __usb_hcd_giveback_urb(struct urb *urb)
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struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
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struct usb_anchor *anchor = urb->anchor;
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int status = urb->unlinked;
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- unsigned long flags;
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urb->hcpriv = NULL;
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if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
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@@ -1766,9 +1765,7 @@ static void __usb_hcd_giveback_urb(struct urb *urb)
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* and no one may trigger the above deadlock situation when
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* running complete() in tasklet.
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*/
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- local_irq_save(flags);
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urb->complete(urb);
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- local_irq_restore(flags);
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usb_anchor_resume_wakeups(anchor);
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atomic_dec(&urb->use_count);
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--
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2.17.1
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