linux.git/drivers/usb/core/hcd.c, branch v5.11 Linux kernel source tree kcov, usb: hide in_serving_softirq checks in __usb_hcd_giveback_urb 2021-01-07T13:17:29+00:00 Andrey Konovalov andreyknvl@google.com 2021-01-05T19:53:42+00:00 e89eed02a5f1b864fa5abafc8e8e71bd9fd66d1f Done opencode in_serving_softirq() checks in in_serving_softirq() to avoid cluttering the code, hide them in kcov helpers instead. Fixes: aee9ddb1d371 ("kcov, usb: only collect coverage from __usb_hcd_giveback_urb in softirq") Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Link: https://lore.kernel.org/r/aeb430c5bb90b0ccdf1ec302c70831c1a47b9c45.1609876340.git.andreyknvl@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Done opencode in_serving_softirq() checks in in_serving_softirq() to avoid
cluttering the code, hide them in kcov helpers instead.

Fixes: aee9ddb1d371 ("kcov, usb: only collect coverage from __usb_hcd_giveback_urb in softirq")
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Link: https://lore.kernel.org/r/aeb430c5bb90b0ccdf1ec302c70831c1a47b9c45.1609876340.git.andreyknvl@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kcov, usb: only collect coverage from __usb_hcd_giveback_urb in softirq 2020-10-28T12:10:54+00:00 Andrey Konovalov andreyknvl@google.com 2020-10-16T13:57:45+00:00 aee9ddb1d3718d3ba05b50c51622d7792ae749c9 Currently there's a KCOV remote coverage collection section in __usb_hcd_giveback_urb(). Initially that section was added based on the assumption that usb_hcd_giveback_urb() can only be called in interrupt context as indicated by a comment before it. This is what happens when syzkaller is fuzzing the USB stack via the dummy_hcd driver. As it turns out, it's actually valid to call usb_hcd_giveback_urb() in task context, provided that the caller turned off the interrupts; USB/IP does exactly that. This can lead to a nested KCOV remote coverage collection sections both trying to collect coverage in task context. This isn't supported by KCOV, and leads to a WARNING. Change __usb_hcd_giveback_urb() to only call kcov_remote_*() callbacks when it's being executed in a softirq. As the result, the coverage from USB/IP related usb_hcd_giveback_urb() calls won't be collected, but the WARNING is fixed. A potential future improvement would be to support nested remote coverage collection sections, but this patch doesn't address that. Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Marco Elver <elver@google.com> Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Link: https://lore.kernel.org/r/f3a7a153f0719cb53ec385b16e912798bd3e4cf9.1602856358.git.andreyknvl@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Currently there's a KCOV remote coverage collection section in
__usb_hcd_giveback_urb(). Initially that section was added based on the
assumption that usb_hcd_giveback_urb() can only be called in interrupt
context as indicated by a comment before it. This is what happens when
syzkaller is fuzzing the USB stack via the dummy_hcd driver.

As it turns out, it's actually valid to call usb_hcd_giveback_urb() in task
context, provided that the caller turned off the interrupts; USB/IP does
exactly that. This can lead to a nested KCOV remote coverage collection
sections both trying to collect coverage in task context. This isn't
supported by KCOV, and leads to a WARNING.

Change __usb_hcd_giveback_urb() to only call kcov_remote_*() callbacks
when it's being executed in a softirq. As the result, the coverage from
USB/IP related usb_hcd_giveback_urb() calls won't be collected, but the
WARNING is fixed.

A potential future improvement would be to support nested remote coverage
collection sections, but this patch doesn't address that.

Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Link: https://lore.kernel.org/r/f3a7a153f0719cb53ec385b16e912798bd3e4cf9.1602856358.git.andreyknvl@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb: core: Replace in_interrupt() in comments 2020-10-28T11:32:59+00:00 Ahmed S. Darwish a.darwish@linutronix.de 2020-10-19T10:06:41+00:00 41631d3616c36305fef7c0e2e6412538a915dc97 The usage of in_interrupt() in drivers is phased out for various reasons. Various comments use !in_interrupt() to describe calling context for functions which might sleep. That's wrong because the calling context has to be preemptible task context, which is not what !in_interrupt() describes. Replace !in_interrupt() with more accurate plain text descriptions. The comment for usb_hcd_poll_rh_status() is misleading as this function is called from all kinds of contexts including preemptible task context. Remove it as there is obviously no restriction. Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: linux-usb@vger.kernel.org Link: https://lore.kernel.org/r/20201019101110.851821025@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The usage of in_interrupt() in drivers is phased out for various reasons.

Various comments use !in_interrupt() to describe calling context for
functions which might sleep. That's wrong because the calling context has
to be preemptible task context, which is not what !in_interrupt()
describes.

Replace !in_interrupt() with more accurate plain text descriptions.

The comment for usb_hcd_poll_rh_status() is misleading as this function is
called from all kinds of contexts including preemptible task
context. Remove it as there is obviously no restriction.

Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: linux-usb@vger.kernel.org
Link: https://lore.kernel.org/r/20201019101110.851821025@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb: hcd: convert tasklets to use new tasklet_setup() API 2020-08-18T11:00:00+00:00 Allen Pais allen.lkml@gmail.com 2020-08-17T09:02:05+00:00 e71ea55a5b6f9162746d6720c07190b0c92e8f9c In preparation for unconditionally passing the struct tasklet_struct pointer to all tasklet callbacks, switch to using the new tasklet_setup() and from_tasklet() to pass the tasklet pointer explicitly. Signed-off-by: Romain Perier <romain.perier@gmail.com> Signed-off-by: Allen Pais <allen.lkml@gmail.com> Link: https://lore.kernel.org/r/20200817090209.26351-4-allen.cryptic@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.

Signed-off-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Link: https://lore.kernel.org/r/20200817090209.26351-4-allen.cryptic@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb: Use fallthrough pseudo-keyword 2020-07-10T06:55:17+00:00 Gustavo A. R. Silva gustavoars@kernel.org 2020-07-07T19:56:07+00:00 0d9b6d49fe39bd397f1d5913b1bfb8c4fdef0255 Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Link: https://lore.kernel.org/r/20200707195607.GA4198@embeddedor Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200707195607.GA4198@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb: core: kcov: collect coverage from usb complete callback 2020-06-05T02:06:20+00:00 Andrey Konovalov andreyknvl@google.com 2020-06-04T23:46:08+00:00 76e278d6b50534092038d4117d7a2687af034107 This patch adds kcov_remote_start/stop() callbacks around the urb complete() callback that is executed in softirq context when dummy_hcd is in use. As the result, kcov can be used to collect coverage from those callbacks, which is used to facilitate coverage-guided fuzzing with syzkaller. Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Marco Elver <elver@google.com> Link: http://lkml.kernel.org/r/4520671eeb604adbc2432c248b0c07fbaa5519ef.1585233617.git.andreyknvl@google.com Link: http://lkml.kernel.org/r/2821d497ac1cdc0efb5e00df30271e4a67fc8009.1584655448.git.andreyknvl@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
This patch adds kcov_remote_start/stop() callbacks around the urb
complete() callback that is executed in softirq context when dummy_hcd is
in use.  As the result, kcov can be used to collect coverage from those
callbacks, which is used to facilitate coverage-guided fuzzing with
syzkaller.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Link: http://lkml.kernel.org/r/4520671eeb604adbc2432c248b0c07fbaa5519ef.1585233617.git.andreyknvl@google.com
Link: http://lkml.kernel.org/r/2821d497ac1cdc0efb5e00df30271e4a67fc8009.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
USB: Fix incorrect DMA allocations for local memory pool drivers 2019-12-11T08:06:41+00:00 Fredrik Noring noring@nocrew.org 2019-12-10T17:29:05+00:00 f8c63edfd78905320e86b6b2be2b7a5ac768fa4e Fix commit 7b81cb6bddd2 ("usb: add a HCD_DMA flag instead of guestimating DMA capabilities") where local memory USB drivers erroneously allocate DMA memory instead of pool memory, causing OHCI Unrecoverable Error, disabled HC died; cleaning up The order between hcd_uses_dma() and hcd->localmem_pool is now arranged as in hcd_buffer_alloc() and hcd_buffer_free(), with the test for hcd->localmem_pool placed first. As an alternative, one might consider adjusting hcd_uses_dma() with static inline bool hcd_uses_dma(struct usb_hcd *hcd) { - return IS_ENABLED(CONFIG_HAS_DMA) && (hcd->driver->flags & HCD_DMA); + return IS_ENABLED(CONFIG_HAS_DMA) && + (hcd->driver->flags & HCD_DMA) && + (hcd->localmem_pool == NULL); } One can also consider unsetting HCD_DMA for local memory pool drivers. Fixes: 7b81cb6bddd2 ("usb: add a HCD_DMA flag instead of guestimating DMA capabilities") Cc: stable <stable@vger.kernel.org> Signed-off-by: Fredrik Noring <noring@nocrew.org> Link: https://lore.kernel.org/r/20191210172905.GA52526@sx9 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Fix commit 7b81cb6bddd2 ("usb: add a HCD_DMA flag instead of
guestimating DMA capabilities") where local memory USB drivers
erroneously allocate DMA memory instead of pool memory, causing

	OHCI Unrecoverable Error, disabled
	HC died; cleaning up

The order between hcd_uses_dma() and hcd->localmem_pool is now
arranged as in hcd_buffer_alloc() and hcd_buffer_free(), with the
test for hcd->localmem_pool placed first.

As an alternative, one might consider adjusting hcd_uses_dma() with

 static inline bool hcd_uses_dma(struct usb_hcd *hcd)
 {
-	return IS_ENABLED(CONFIG_HAS_DMA) && (hcd->driver->flags & HCD_DMA);
+	return IS_ENABLED(CONFIG_HAS_DMA) &&
+		(hcd->driver->flags & HCD_DMA) &&
+		(hcd->localmem_pool == NULL);
 }

One can also consider unsetting HCD_DMA for local memory pool drivers.

Fixes: 7b81cb6bddd2 ("usb: add a HCD_DMA flag instead of guestimating DMA capabilities")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Fredrik Noring <noring@nocrew.org>
Link: https://lore.kernel.org/r/20191210172905.GA52526@sx9
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb: core: Remove redundant vmap checks 2019-10-31T13:40:43+00:00 Kees Cook keescook@chromium.org 2019-10-29T21:34:23+00:00 b3d53f5fce5d07b4981f0f4f93e579e389a99b07 Now that the vmap area checks are being performed in the DMA infrastructure directly, there is no need to repeat them in USB. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de> 
Now that the vmap area checks are being performed in the DMA
infrastructure directly, there is no need to repeat them in USB.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
usb: core: phy: add support for PHY calibration 2019-09-03T13:54:55+00:00 Marek Szyprowski m.szyprowski@samsung.com 2019-08-29T05:30:27+00:00 34c7ed72f4f04e73901ca6ec2e1db6c040495935 Some PHYs (for example Exynos5 USB3.0 DRD PHY) require calibration to be done after every USB HCD reset. Generic PHY framework has been already extended with phy_calibrate() function in commit 36914111e682 ("drivers: phy: add calibrate method"). This patch adds support for it to generic PHY handling code in USB HCD core. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Anand Moon <linux.amoon@gmail.com> Tested-by: Jochen Sprickerhof <jochen@sprickerhof.de> Link: https://lore.kernel.org/r/20190829053028.32438-2-m.szyprowski@samsung.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Some PHYs (for example Exynos5 USB3.0 DRD PHY) require calibration to be
done after every USB HCD reset. Generic PHY framework has been already
extended with phy_calibrate() function in commit 36914111e682 ("drivers:
phy: add calibrate method"). This patch adds support for it to generic
PHY handling code in USB HCD core.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Anand Moon <linux.amoon@gmail.com>
Tested-by: Jochen Sprickerhof <jochen@sprickerhof.de>
Link: https://lore.kernel.org/r/20190829053028.32438-2-m.szyprowski@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb: remove a stale comment in hcd_alloc_coherent 2019-09-03T13:26:11+00:00 Christoph Hellwig hch@lst.de 2019-09-03T08:46:13+00:00 ac2658e0d9f0461e730cbc343231dad304fb2f4f Now that we have the local memory pool implemented there is no need to use dma_declare_coherent_memory. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20190903084615.19161-5-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Now that we have the local memory pool implemented there is no
need to use dma_declare_coherent_memory.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20190903084615.19161-5-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>