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code
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This is a collection of three fixes for small annoyances.
Two of these are already pending in other trees, but I really don't want
to release another -rc with these issues pending, so I picked up the
patches for these things directly. We'll end up with duplicate commits
eventually, I prefer that over having these issues pending.
The third one is just me getting rid of another BUG_ON() just because it
was reported and I dislike those things so much.
* merge 'hot-fixes' branch:
ida: don't use BUG_ON() for debugging
drm/aperture: Run fbdev removal before internal helpers
ptrace: fix clearing of JOBCTL_TRACED in ptrace_unfreeze_traced()
Pull dmaengine fixes from Vinod Koul:
"One core fix for DMA_INTERRUPT and rest driver fixes.
Core:
- Revert verification of DMA_INTERRUPT capability as that was
incorrect
Bunch of driver fixes for:
- ti: refcount and put_device leak
- qcom_bam: runtime pm overflow
- idxd: force wq context cleanup and call idxd_enable_system_pasid()
on success
- dw-axi-dmac: RMW on channel suspend register
- imx-sdma: restart cyclic channel when enabled
- at_xdma: error handling for at_xdmac_alloc_desc
- pl330: lockdep warning
- lgm: error handling path in probe
- allwinner: Fix min/max typo in binding"
* tag 'dmaengine-fix-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine:
dt-bindings: dma: allwinner,sun50i-a64-dma: Fix min/max typo
dmaengine: lgm: Fix an error handling path in intel_ldma_probe()
dmaengine: pl330: Fix lockdep warning about non-static key
dmaengine: idxd: Only call idxd_enable_system_pasid() if succeeded in enabling SVA feature
dmaengine: at_xdma: handle errors of at_xdmac_alloc_desc() correctly
dmaengine: imx-sdma: only restart cyclic channel when enabled
dmaengine: dw-axi-dmac: Fix RMW on channel suspend register
dmaengine: idxd: force wq context cleanup on device disable path
dmaengine: qcom: bam_dma: fix runtime PM underflow
dmaengine: imx-sdma: Allow imx8m for imx7 FW revs
dmaengine: Revert "dmaengine: add verification of DMA_INTERRUPT capability for dmatest"
dmaengine: ti: Add missing put_device in ti_dra7_xbar_route_allocate
dmaengine: ti: Fix refcount leak in ti_dra7_xbar_route_allocate
This is another old BUG_ON() that just shouldn't exist (see also commit
a382f8fee42c: "signal handling: don't use BUG_ON() for debugging").
In fact, as Matthew Wilcox points out, this condition shouldn't really
even result in a warning, since a negative id allocation result is just
a normal allocation failure:
"I wonder if we should even warn here -- sure, the caller is trying to
free something that wasn't allocated, but we don't warn for
kfree(NULL)"
and goes on to point out how that current error check is only causing
people to unnecessarily do their own index range checking before freeing
it.
This was noted by Itay Iellin, because the bluetooth HCI socket cookie
code does *not* do that range checking, and ends up just freeing the
error case too, triggering the BUG_ON().
The HCI code requires CAP_NET_RAW, and seems to just result in an ugly
splat, but there really is no reason to BUG_ON() here, and we have
generally striven for allocation models where it's always ok to just do
free(alloc());
even if the allocation were to fail for some random reason (usually
obviously that "random" reason being some resource limit).
Fixes: 88eca0207cf1 ("ida: simplified functions for id allocation")
Reported-by: Itay Iellin <ieitayie@gmail.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull staging driver fix from Greg KH:
"Here is a single staging driver fix for a reported problem that showed
up in 5.19-rc1 in the wlan-ng driver. It has been in linux-next for a
week with no reported problems"
* tag 'staging-5.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging/wlan-ng: get the correct struct hfa384x in work callback
The conditional block for variants with a second clock should have set
minItems, not maxItems, which was already 2. Since clock-names requires
two items, this typo should not have caused any problems.
Fixes: edd14218bd66 ("dt-bindings: dmaengine: Convert Allwinner A31 and A64 DMA to a schema")
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220702031903.21703-1-samuel@sholland.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Always run fbdev removal first to remove simpledrm via sysfb_disable().
This clears the internal state.
The later call to drm_aperture_detach_drivers() then does nothing.
Otherwise, with drm_aperture_detach_drivers() running first, the call to
sysfb_disable() uses inconsistent state.
Example backtrace show below:
BUG: KASAN: use-after-free in device_del+0x79/0x5f0
Read of size 8 at addr ffff888108185050 by task systemd-udevd/311
CPU: 0 PID: 311 Comm: systemd-udevd Tainted: G E 5.19.0-rc2-1-default+ #1689
Hardware name: HP ProLiant DL120 G7, BIOS J01 04/21/2011
Call Trace:
device_del+0x79/0x5f0
platform_device_del.part.0+0x19/0xe0
platform_device_unregister+0x1c/0x30
sysfb_disable+0x2d/0x70
remove_conflicting_framebuffers+0x1c/0xf0
remove_conflicting_pci_framebuffers+0x130/0x1a0
drm_aperture_remove_conflicting_pci_framebuffers+0x86/0xb0
mgag200_pci_probe+0x2d/0x140 [mgag200]
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 873eb3b11860 ("fbdev: Disable sysfb device registration when removing conflicting FBs")
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Changcheng Deng <deng.changcheng@zte.com.cn>
Reviewed-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull char/misc driver fixes from Greg KH:
"Here are four small char/misc driver fixes for 5.19-rc6 to resolve
some reported issues. They only affect two drivers:
- rtsx_usb: fix for of-reported DMA warning error, the driver was
handling memory buffers in odd ways, it has now been fixed up to be
much simpler and correct by Shuah.
- at25 eeprom driver bugfix for reported problem
All of these have been in linux-next for a week with no reported
problems"
* tag 'char-misc-5.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
misc: rtsx_usb: set return value in rsp_buf alloc err path
misc: rtsx_usb: use separate command and response buffers
misc: rtsx_usb: fix use of dma mapped buffer for usb bulk transfer
eeprom: at25: Rework buggy read splitting
hfa384x_usbctlx_completion_task() is bogusly using the reaper BH when
in fact this is the completion_bh. This was reflected when trying
to acquire the hw->ctlxq.lock and getting a failed lockdep class
initialized to it.
Fixes: 9442e81d7e7c ("staging/wlan-ng, prism2usb: replace completion_bh tasklet with work")
Reported-by: syzbot+ce3408364c4a234dd90c@syzkaller.appspotmail.com
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/20220629165225.3436822-1-dave@stgolabs.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ldma_clk_disable() calls both:
clk_disable_unprepare(d->core_clk);
reset_control_assert(d->rst);
So, should devm_reset_control_get_optional() fail, core_clk should not
be prepare_enable'd before it, otherwise it will never be
disable_unprepare'd.
Reorder the code to handle the error handling path as expected.
Fixes: 32d31c79a1a4 ("dmaengine: Add Intel LGM SoC DMA support.")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/18504549bc4d2b62a72a02cb22a2e4d8e6a58720.1653241224.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>
CI reported the following splat while running the strace testsuite:
WARNING: CPU: 1 PID: 3570031 at kernel/ptrace.c:272 ptrace_check_attach+0x12e/0x178
CPU: 1 PID: 3570031 Comm: strace Tainted: G OE 5.19.0-20220624.rc3.git0.ee819a77d4e7.300.fc36.s390x #1
Hardware name: IBM 3906 M04 704 (z/VM 7.1.0)
Call Trace:
[<00000000ab4b645a>] ptrace_check_attach+0x132/0x178
([<00000000ab4b6450>] ptrace_check_attach+0x128/0x178)
[<00000000ab4b6cde>] __s390x_sys_ptrace+0x86/0x160
[<00000000ac03fcec>] __do_syscall+0x1d4/0x200
[<00000000ac04e312>] system_call+0x82/0xb0
Last Breaking-Event-Address:
[<00000000ab4ea3c8>] wait_task_inactive+0x98/0x190
This is because JOBCTL_TRACED is set, but the task is not in TASK_TRACED
state. Caused by ptrace_unfreeze_traced() which does:
task->jobctl &= ~TASK_TRACED
but it should be:
task->jobctl &= ~JOBCTL_TRACED
Fixes: 31cae1eaae4f ("sched,signal,ptrace: Rework TASK_TRACED, TASK_STOPPED state")
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Tested-by: Alexander Gordeev <agordeev@linux.ibm.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull io_uring fix from Jens Axboe:
"A single fix for an issue that came up yesterday that we should plug
for -rc6.
This is a regression introduced in this cycle"
* tag 'io_uring-5.19-2022-07-09' of git://git.kernel.dk/linux-block:
io_uring: check that we have a file table when allocating update slots
Set return value in rsp_buf alloc error path before going to
error handling.
drivers/misc/cardreader/rtsx_usb.c:639:6: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
if (!ucr->rsp_buf)
^~~~~~~~~~~~~
drivers/misc/cardreader/rtsx_usb.c:678:9: note: uninitialized use occurs here
return ret;
^~~
drivers/misc/cardreader/rtsx_usb.c:639:2: note: remove the 'if' if its condition is always false
if (!ucr->rsp_buf)
^~~~~~~~~~~~~~~~~~
drivers/misc/cardreader/rtsx_usb.c:622:9: note: initialize the variable 'ret' to silence this warning
int ret;
^
= 0
Fixes: 3776c7855985 ("misc: rtsx_usb: use separate command and response buffers")
Reported-by: kernel test robot <lkp@intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20220701165352.15687-1-skhan@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>