The logic to calculate the subset of stream parameters supported by all
DAIs associated with a PCM stream is nontrivial. Export a helper
function so it can be used to set up simple codec2codec DAI links.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20200305051143.60691-3-samuel@sholland.org
Signed-off-by: Mark Brown <broonie@kernel.org>
It can be useful to derive min/max rates of a snd_pcm_hardware without
having a snd_pcm_runtime, such as before constructing an ASoC DAI link.
Create a new helper that takes a pointer to a snd_pcm_hardware directly,
and refactor the original function as a wrapper around it, to avoid
needing to update any call sites.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20200305051143.60691-2-samuel@sholland.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Looks like there are some unused headers, remove them.
Seems to be missed while moving to mfd.
Reported-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200306132806.19684-3-srinivas.kandagatla@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The bfq_find_set_group() function takes as input a blkcg (which represents
a cgroup) and retrieves the corresponding bfq_group, then it updates the
bfq internal group hierarchy (see comments inside the function for why
this is needed) and finally it returns the bfq_group.
In the hierarchy update cycle, the pointer holding the correct bfq_group
that has to be returned is mistakenly used to traverse the hierarchy
bottom to top, meaning that in each iteration it gets overwritten with the
parent of the current group. Since the update cycle stops at root's
children (depth = 2), the overwrite becomes a problem only if the blkcg
describes a cgroup at a hierarchy level deeper than that (depth > 2). In
this case the root's child that happens to be also an ancestor of the
correct bfq_group is returned. The main consequence is that processes
contained in a cgroup at depth greater than 2 are wrongly placed in the
group described above by BFQ.
This commits fixes this problem by using a different bfq_group pointer in
the update cycle in order to avoid the overwrite of the variable holding
the original group reference.
Reported-by: Kwon Je Oh <kwonje.oh2@gmail.com>
Signed-off-by: Carlo Nonato <carlo.nonato95@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Get rid of those warnings by adding extra blank lines:
Documentation/driver-api/dmaengine/provider.rst:270: WARNING: Unexpected indentation.
Documentation/driver-api/dmaengine/provider.rst:273: WARNING: Block quote ends without a blank line; unexpected unindent.
Documentation/driver-api/dmaengine/provider.rst:288: WARNING: Unexpected indentation.
Documentation/driver-api/dmaengine/provider.rst:290: WARNING: Block quote ends without a blank line; unexpected unindent.
While here, use parenthesis after get_metadata_ptr/set_metadata_len,
as, if some day someone adds a kerneldoc markup for those, it
should automatically generate a cross-reference to them.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/62cf2a87b379a92c9c0e5a40c2ae8a138b01fe0a.1583250595.git.mchehab+huawei@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
drivers/dma/fsl-dpaa2-qdma/dpaa2-qdma.c: In function dpaa2_qdma_shutdown:
drivers/dma/fsl-dpaa2-qdma/dpaa2-qdma.c:795:28: warning: variable dpaa2_qdma set but not used [-Wunused-but-set-variable]
commit 3e0ca3c38d ("dmaengine: fsl-dpaa2-qdma: Adding shutdown hook")
involved this, remove it.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20200303131347.28392-1-yuehaibing@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
If the firmware is in a bad state or not initialized fully, sending
the DBGC_SUSPEND_RESUME command fails but we can still collect logs.
Instead of aborting the entire dump process, simply ignore the error.
By removing the last callpoint that was checking the return value, we
can also convert the function to return void.
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Fixes: 576058330f ("iwlwifi: dbg: support debug recording suspend resume command")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200306151129.dcec37b2efd4.I8dcd190431d110a6a0e88095ce93591ccfb3d78d@changeid
The TLV offset is only used to read registers, while the offset used for
the FIFO addresses are hard coded in the driver and not given by the
TLV.
If we try to apply the TLV offset when reading the FIFOs, we'll read
from invalid addresses, causing the driver to hang.
Signed-off-by: Mordechay Goodstein <mordechay.goodstein@intel.com>
Fixes: 8d7dea25ad ("iwlwifi: dbg_ini: implement Rx fifos dump")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200306151129.fbab869c26fa.I4ddac20d02f9bce41855a816aa6855c89bc3874e@changeid
We were erroneously checking the length of the tlv instead of checking
the pointer returned by kmemdup() when allocating dbg_conf_tlv[].
This was probably a typo. Fix it by checking the returned pointer
instead of the length.
Reported-by: Markus Elfring <Markus.Elfring@web.de>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200306151128.06e00e6e980f.I9a890ce83493b79892a5f690d12016525317fa7e@changeid
The AP may set the LDPC capability only in HE (IEEE80211_HE_PHY_CAP1),
but we were checking it only in the HT capabilities.
If we don't use this capability when required, the DSP gets the wrong
configuration in HE and doesn't work properly.
Signed-off-by: Mordechay Goodstein <mordechay.goodstein@intel.com>
Fixes: befebbb30a ("iwlwifi: rs: consider LDPC capability in case of HE")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200306151128.492d167c1a25.I1ad1353dbbf6c99ae57814be750f41a1c9f7f4ac@changeid
drivers/base/arch_topology.c is only built if CONFIG_GENERIC_ARCH_TOPOLOGY=y,
resulting in such build failures:
cpufreq_cooling.c:(.text+0x1e7): undefined reference to `arch_set_thermal_pressure'
Move it to sched/core.c instead, and keep it enabled on x86 despite
us not having a arch_scale_thermal_pressure() facility there, to
build-test this thing.
Cc: Thara Gopinath <thara.gopinath@linaro.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
drm_fb_helper tasks are completed now hence remove them from
todo list.
Changes since v1:
* remove entire drm_fb_helper tasks from todo list. Daniel's
"64914da24e drm/fbdev-helper: don't force restores" already fixes
first one (Daniel)
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200305120434.111091-8-pankaj.laxminarayan.bharadiya@intel.com
drm_fb_helper_single_add_all_connectors(),
drm_fb_helper_add_one_connector()
and drm_fb_helper_remove_one_connector() don't keep an array of
connectors anymore and are just dummy. Now we have no callers to these
functions hence remove them.
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200305120434.111091-7-pankaj.laxminarayan.bharadiya@intel.com
drm_fb_helper_{add,remove}_one_connector() and
drm_fb_helper_single_add_all_connectors() are dummy functions now
and serve no purpose. Hence remove their calls.
This is the preparatory step for removing the
drm_fb_helper_{add,remove}_one_connector() functions from
drm_fb_helper.h
This removal is done using below sementic patch and unused variable
compilation warnings are fixed manually.
@@
@@
- drm_fb_helper_single_add_all_connectors(...);
@@
expression e1;
statement S;
@@
- e1 = drm_fb_helper_single_add_all_connectors(...);
- S
@@
@@
- drm_fb_helper_add_one_connector(...);
@@
@@
- drm_fb_helper_remove_one_connector(...);
Changes since v1:
* Squashed warning fixes into the patch that introduced the
warnings (into 5/7) (Laurent, Emil, Lyude)
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200305120434.111091-6-pankaj.laxminarayan.bharadiya@intel.com
drm_fb_helper_{add,remove}_one_connector() are dummy functions now
and serve no purpose. Hence remove their calls.
This is the preparatory step for removing the
drm_fb_helper_{add,remove}_one_connector() functions from
drm_fb_helper.h
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200305120434.111091-5-pankaj.laxminarayan.bharadiya@intel.com
drm_fb_helper_{add,remove}_one_connector() are dummy functions now
and serve no purpose. Hence remove their calls.
This is the preparatory step for removing the
drm_fb_helper_{add,remove}_one_connector() functions from
drm_fb_helper.h
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200305120434.111091-4-pankaj.laxminarayan.bharadiya@intel.com
drm_fb_helper_{add,remove}_one_connector() are dummy functions now
and serve no purpose. Hence remove their calls.
This is the preparatory step for removing the
drm_fb_helper_{add,remove}_one_connector() functions from
drm_fb_helper.h
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200305120434.111091-3-pankaj.laxminarayan.bharadiya@intel.com
The max connector argument for drm_fb_helper_init() isn't used anymore
hence remove it.
All the drm_fb_helper_init() calls are modified with below sementic
patch.
@@
expression E1, E2, E3;
@@
- drm_fb_helper_init(E1,E2, E3)
+ drm_fb_helper_init(E1,E2)
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200305120434.111091-2-pankaj.laxminarayan.bharadiya@intel.com
Merge misc fixes from Andrew Morton:
"7 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
arch/Kconfig: update HAVE_RELIABLE_STACKTRACE description
mm, hotplug: fix page online with DEBUG_PAGEALLOC compiled but not enabled
mm/z3fold.c: do not include rwlock.h directly
fat: fix uninit-memory access for partial initialized inode
mm: avoid data corruption on CoW fault into PFN-mapped VMA
mm: fix possible PMD dirty bit lost in set_pmd_migration_entry()
mm, numa: fix bad pmd by atomically check for pmd_trans_huge when marking page tables prot_numa
The existing tests attempt to check that JMP32 JSET ignores the upper
bits in the operand registers. However, the tests missed one such bug in
the x32 JIT that is only uncovered when a previous instruction pollutes
the upper 32 bits of the registers.
This patch adds a new test case that catches the bug by first executing
a 64-bit JSET to pollute the upper 32-bits of the temporary registers,
followed by a 32-bit JSET which should ignore the upper 32 bits.
Co-developed-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Luke Nelson <luke.r.nels@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200305234416.31597-2-luke.r.nels@gmail.com
The current x32 BPF JIT is incorrect for JMP32 JSET BPF_X when the upper
32 bits of operand registers are non-zero in certain situations.
The problem is in the following code:
case BPF_JMP | BPF_JSET | BPF_X:
case BPF_JMP32 | BPF_JSET | BPF_X:
...
/* and dreg_lo,sreg_lo */
EMIT2(0x23, add_2reg(0xC0, sreg_lo, dreg_lo));
/* and dreg_hi,sreg_hi */
EMIT2(0x23, add_2reg(0xC0, sreg_hi, dreg_hi));
/* or dreg_lo,dreg_hi */
EMIT2(0x09, add_2reg(0xC0, dreg_lo, dreg_hi));
This code checks the upper bits of the operand registers regardless if
the BPF instruction is BPF_JMP32 or BPF_JMP64. Registers dreg_hi and
dreg_lo are not loaded from the stack for BPF_JMP32, however, they can
still be polluted with values from previous instructions.
The following BPF program demonstrates the bug. The jset64 instruction
loads the temporary registers and performs the jump, since ((u64)r7 &
(u64)r8) is non-zero. The jset32 should _not_ be taken, as the lower
32 bits are all zero, however, the current JIT will take the branch due
the pollution of temporary registers from the earlier jset64.
mov64 r0, 0
ld64 r7, 0x8000000000000000
ld64 r8, 0x8000000000000000
jset64 r7, r8, 1
exit
jset32 r7, r8, 1
mov64 r0, 2
exit
The expected return value of this program is 2; under the buggy x32 JIT
it returns 0. The fix is to skip using the upper 32 bits for jset32 and
compare the upper 32 bits for jset64 only.
All tests in test_bpf.ko and selftests/bpf/test_verifier continue to
pass with this change.
We found this bug using our automated verification tool, Serval.
Fixes: 69f827eb6e ("x32: bpf: implement jitting of JMP32")
Co-developed-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Luke Nelson <luke.r.nels@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200305234416.31597-1-luke.r.nels@gmail.com
Check the edge case where batch_start_offset sits exactly on the batch
size.
v2: add new range_overflows variant to capture the special case where
the size is permitted to be zero, like with batch_len.
v3: other way around. the common case is the exclusive one which should
just be >=, with that we then just need to convert the three odd ball
cases that don't apply to use the new inclusive _end version.
Testcase: igt/gem_exec_params/invalid-batch-start-offset
Fixes: 0b5372727b ("drm/i915/cmdparser: Use cached vmappings")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200306094735.258285-1-matthew.auld@intel.com
Since commit 3bc3206e1c ("serial: fsl_lpuart: Remove the alias node
dependence") the port line number can also be allocated by IDA, but in
case of an error the ID will no be removed again. More importantly, any
ID will be freed in remove(), even if it wasn't allocated but instead
fetched by of_alias_get_id(). If it was not allocated by IDA there will
be a warning:
WARN(1, "ida_free called for id=%d which is not allocated.\n", id);
Move the ID allocation more to the end of the probe() so that we still
can use plain return in the first error cases.
Fixes: 3bc3206e1c ("serial: fsl_lpuart: Remove the alias node dependence")
Signed-off-by: Michael Walle <michael@walle.cc>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200303174306.6015-3-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit a659652f61.
This broke the earlycon on LS1021A processors because the order of the
earlycon_setup() functions were changed. Before the commit the normal
lpuart32_early_console_setup() was called. After the commit the
lpuart32_imx_early_console_setup() is called instead.
Fixes: a659652f61 ("tty: serial: fsl_lpuart: drop EARLYCON_DECLARE")
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200303174306.6015-2-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On Apple devices the _CRS method returns an empty resource template, and
the resource settings are instead provided by the _DSM method. But
commit 33364d63c7 (serdev: Add ACPI
devices by ResourceSource field) changed the search for serdev devices
to require valid, non-empty resource template, thereby breaking Apple
devices and causing bluetooth devices to not be found.
This expands the check so that if we don't find a valid template, and
we're on an Apple machine, then just check for the device being an
immediate child of the controller and having a "baud" property.
Cc: <stable@vger.kernel.org> # 5.5
Fixes: 33364d63c7 ("serdev: Add ACPI devices by ResourceSource field")
Signed-off-by: Ronald Tschalär <ronald@innovation.ch>
Link: https://lore.kernel.org/r/20200211194723.486217-1-ronald@innovation.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
save_stack_trace_tsk_reliable() is not the only function providing the
reliable stack traces anymore. Architecture might define ARCH_STACKWALK
which provides a newer stack walking interface and has
arch_stack_walk_reliable() function. Update the description accordingly.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: http://lkml.kernel.org/r/20200120154042.9934-1-mbenes@suse.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit cd02cf1ace ("mm/hotplug: fix an imbalance with DEBUG_PAGEALLOC")
fixed memory hotplug with debug_pagealloc enabled, where onlining a page
goes through page freeing, which removes the direct mapping. Some arches
don't like when the page is not mapped in the first place, so
generic_online_page() maps it first. This is somewhat wasteful, but
better than special casing page freeing fast paths.
The commit however missed that DEBUG_PAGEALLOC configured doesn't mean
it's actually enabled. One has to test debug_pagealloc_enabled() since
031bc5743f ("mm/debug-pagealloc: make debug-pagealloc boottime
configurable"), or alternatively debug_pagealloc_enabled_static() since
8e57f8acbb ("mm, debug_pagealloc: don't rely on static keys too early"),
but this is not done.
As a result, a s390 kernel with DEBUG_PAGEALLOC configured but not enabled
will crash:
Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 0000000000000000 TEID: 0000000000000483
Fault in home space mode while using kernel ASCE.
AS:0000001ece13400b R2:000003fff7fd000b R3:000003fff7fcc007 S:000003fff7fd7000 P:000000000000013d
Oops: 0004 ilc:2 [#1] SMP
CPU: 1 PID: 26015 Comm: chmem Kdump: loaded Tainted: GX 5.3.18-5-default #1 SLE15-SP2 (unreleased)
Krnl PSW : 0704e00180000000 0000001ecd281b9e (__kernel_map_pages+0x166/0x188)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
Krnl GPRS: 0000000000000000 0000000000000800 0000400b00000000 0000000000000100
0000000000000001 0000000000000000 0000000000000002 0000000000000100
0000001ece139230 0000001ecdd98d40 0000400b00000100 0000000000000000
000003ffa17e4000 001fffe0114f7d08 0000001ecd4d93ea 001fffe0114f7b20
Krnl Code: 0000001ecd281b8e: ec17ffff00d8 ahik %r1,%r7,-1
0000001ecd281b94: ec111dbc0355 risbg %r1,%r1,29,188,3
>0000001ecd281b9e: 94fb5006 ni 6(%r5),251
0000001ecd281ba2: 41505008 la %r5,8(%r5)
0000001ecd281ba6: ec51fffc6064 cgrj %r5,%r1,6,1ecd281b9e
0000001ecd281bac: 1a07 ar %r0,%r7
0000001ecd281bae: ec03ff584076 crj %r0,%r3,4,1ecd281a5e
Call Trace:
[<0000001ecd281b9e>] __kernel_map_pages+0x166/0x188
[<0000001ecd4d9516>] online_pages_range+0xf6/0x128
[<0000001ecd2a8186>] walk_system_ram_range+0x7e/0xd8
[<0000001ecda28aae>] online_pages+0x2fe/0x3f0
[<0000001ecd7d02a6>] memory_subsys_online+0x8e/0xc0
[<0000001ecd7add42>] device_online+0x5a/0xc8
[<0000001ecd7d0430>] state_store+0x88/0x118
[<0000001ecd5b9f62>] kernfs_fop_write+0xc2/0x200
[<0000001ecd5064b6>] vfs_write+0x176/0x1e0
[<0000001ecd50676a>] ksys_write+0xa2/0x100
[<0000001ecda315d4>] system_call+0xd8/0x2c8
Fix this by checking debug_pagealloc_enabled_static() before calling
kernel_map_pages(). Backports for kernel before 5.5 should use
debug_pagealloc_enabled() instead. Also add comments.
Fixes: cd02cf1ace ("mm/hotplug: fix an imbalance with DEBUG_PAGEALLOC")
Reported-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: <stable@vger.kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/20200224094651.18257-1-vbabka@suse.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
rwlock.h should not be included directly. Instead linux/splinlock.h
should be included. One thing it does is to break the RT build.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200224133631.1510569-1-bigeasy@linutronix.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When get an error in the middle of reading an inode, some fields in the
inode might be still not initialized. And then the evict_inode path may
access those fields via iput().
To fix, this makes sure that inode fields are initialized.
Reported-by: syzbot+9d82b8de2992579da5d0@syzkaller.appspotmail.com
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/871rqnreqx.fsf@mail.parknet.co.jp
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Moyer has reported that one of xfstests triggers a warning when run
on DAX-enabled filesystem:
WARNING: CPU: 76 PID: 51024 at mm/memory.c:2317 wp_page_copy+0xc40/0xd50
...
wp_page_copy+0x98c/0xd50 (unreliable)
do_wp_page+0xd8/0xad0
__handle_mm_fault+0x748/0x1b90
handle_mm_fault+0x120/0x1f0
__do_page_fault+0x240/0xd70
do_page_fault+0x38/0xd0
handle_page_fault+0x10/0x30
The warning happens on failed __copy_from_user_inatomic() which tries to
copy data into a CoW page.
This happens because of race between MADV_DONTNEED and CoW page fault:
CPU0 CPU1
handle_mm_fault()
do_wp_page()
wp_page_copy()
do_wp_page()
madvise(MADV_DONTNEED)
zap_page_range()
zap_pte_range()
ptep_get_and_clear_full()
<TLB flush>
__copy_from_user_inatomic()
sees empty PTE and fails
WARN_ON_ONCE(1)
clear_page()
The solution is to re-try __copy_from_user_inatomic() under PTL after
checking that PTE is matches the orig_pte.
The second copy attempt can still fail, like due to non-readable PTE, but
there's nothing reasonable we can do about, except clearing the CoW page.
Reported-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Jeff Moyer <jmoyer@redhat.com>
Cc: <stable@vger.kernel.org>
Cc: Justin He <Justin.He@arm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: http://lkml.kernel.org/r/20200218154151.13349-1-kirill.shutemov@linux.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In set_pmd_migration_entry(), pmdp_invalidate() is used to change PMD
atomically. But the PMD is read before that with an ordinary memory
reading. If the THP (transparent huge page) is written between the PMD
reading and pmdp_invalidate(), the PMD dirty bit may be lost, and cause
data corruption. The race window is quite small, but still possible in
theory, so need to be fixed.
The race is fixed via using the return value of pmdp_invalidate() to get
the original content of PMD, which is a read/modify/write atomic
operation. So no THP writing can occur in between.
The race has been introduced when the THP migration support is added in
the commit 616b837153 ("mm: thp: enable thp migration in generic path").
But this fix depends on the commit d52605d7cb ("mm: do not lose dirty
and accessed bits in pmdp_invalidate()"). So it's easy to be backported
after v4.16. But the race window is really small, so it may be fine not
to backport the fix at all.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Link: http://lkml.kernel.org/r/20200220075220.2327056-1-ying.huang@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
: A user reported a bug against a distribution kernel while running a
: proprietary workload described as "memory intensive that is not swapping"
: that is expected to apply to mainline kernels. The workload is
: read/write/modifying ranges of memory and checking the contents. They
: reported that within a few hours that a bad PMD would be reported followed
: by a memory corruption where expected data was all zeros. A partial
: report of the bad PMD looked like
:
: [ 5195.338482] ../mm/pgtable-generic.c:33: bad pmd ffff8888157ba008(000002e0396009e2)
: [ 5195.341184] ------------[ cut here ]------------
: [ 5195.356880] kernel BUG at ../mm/pgtable-generic.c:35!
: ....
: [ 5195.410033] Call Trace:
: [ 5195.410471] [<ffffffff811bc75d>] change_protection_range+0x7dd/0x930
: [ 5195.410716] [<ffffffff811d4be8>] change_prot_numa+0x18/0x30
: [ 5195.410918] [<ffffffff810adefe>] task_numa_work+0x1fe/0x310
: [ 5195.411200] [<ffffffff81098322>] task_work_run+0x72/0x90
: [ 5195.411246] [<ffffffff81077139>] exit_to_usermode_loop+0x91/0xc2
: [ 5195.411494] [<ffffffff81003a51>] prepare_exit_to_usermode+0x31/0x40
: [ 5195.411739] [<ffffffff815e56af>] retint_user+0x8/0x10
:
: Decoding revealed that the PMD was a valid prot_numa PMD and the bad PMD
: was a false detection. The bug does not trigger if automatic NUMA
: balancing or transparent huge pages is disabled.
:
: The bug is due a race in change_pmd_range between a pmd_trans_huge and
: pmd_nond_or_clear_bad check without any locks held. During the
: pmd_trans_huge check, a parallel protection update under lock can have
: cleared the PMD and filled it with a prot_numa entry between the transhuge
: check and the pmd_none_or_clear_bad check.
:
: While this could be fixed with heavy locking, it's only necessary to make
: a copy of the PMD on the stack during change_pmd_range and avoid races. A
: new helper is created for this as the check if quite subtle and the
: existing similar helpful is not suitable. This passed 154 hours of
: testing (usually triggers between 20 minutes and 24 hours) without
: detecting bad PMDs or corruption. A basic test of an autonuma-intensive
: workload showed no significant change in behaviour.
Although Mel withdrew the patch on the face of LKML comment
https://lkml.org/lkml/2017/4/10/922 the race window aforementioned is
still open, and we have reports of Linpack test reporting bad residuals
after the bad PMD warning is observed. In addition to that, bad
rss-counter and non-zero pgtables assertions are triggered on mm teardown
for the task hitting the bad PMD.
host kernel: mm/pgtable-generic.c:40: bad pmd 00000000b3152f68(8000000d2d2008e7)
....
host kernel: BUG: Bad rss-counter state mm:00000000b583043d idx:1 val:512
host kernel: BUG: non-zero pgtables_bytes on freeing mm: 4096
The issue is observed on a v4.18-based distribution kernel, but the race
window is expected to be applicable to mainline kernels, as well.
[akpm@linux-foundation.org: fix comment typo, per Rafael]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Cc: <stable@vger.kernel.org>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Link: http://lkml.kernel.org/r/20200216191800.22423-1-aquini@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert a problematic commit from the 5.3 development
cycle (Brendan Higgins).
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Merge tag 'devprop-5.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull device properties framework fix from Rafael Wysocki:
"Revert a problematic commit from the 5.3 development cycle (Brendan
Higgins)"
* tag 'devprop-5.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Revert "software node: Simplify software_node_release() function"
Fix Sphinx format warinings in an ACPI fan document added
recently (Randy Dunlap).
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Merge tag 'acpi-5.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI documentation fix from Rafael Wysocki:
"Fix Sphinx format warinings in an ACPI fan document added recently
(Randy Dunlap)"
* tag 'acpi-5.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Documentation/admin-guide/acpi: fix fan_performance_states.rst warnings
dma-buf:
- fix memory leak
core:
- shmem object mmap fix.
ttm:
- Fix fence leak in ttm_buffer_object_transfer().
amdgpu:
- Gfx reset fix for gfx9, 10
- Fix for gfx10
- DP MST fix
- DCC fix
- Renoir power fixes
- Navi power fix
i915:
- Break up long lists of object reclaim with cond_resched()
- PSR probe fix
- TGL workarounds
- Selftest return value fix
- Drop timeline mutex while waiting for retirement
- Wait for OA configuration completion before writes to OA buffer
virtio:
- Fix resource id creation race in virtio.
- mmap fixes
sun4i:
- Fixes for sun4i VI layer format support.
kirin:
- kirin: Revert "Fix for hikey620 display offset problem"
exynos:
- fix a kernel oops problem in case that driver is loaded as module.
- fix a regulator warning issue when I2C DDC adapter cannot be gathered.
- print out an error message only in error case excepting -EPROBE_DEFER.
mediatek:
- overlay, cursor and gce fixes.
`
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Merge tag 'drm-fixes-2020-03-06' of git://anongit.freedesktop.org/drm/drm
Pull drm fixes from Dave Airlie:
"Weekly fixes round, looks like a few people woke up, got a bunch of
fixes across the drivers. Bit bigger than I'd like but they all seem
fine and hopefully it quiets down now.
sun4i, kirin, mediatek and exynos on the ARM side. virtio-gpu and core
have some mmap fixes, and there is a dma-buf leak. one ttm fence leak
is also fixed.
Otherwise it's mostly amdgpu and i915.
One of the i915 fixes is for a very long latency I was seeing (using
latencytop) running gnome-shell locally when using firefox and eating
nearly all my RAM, it really helps with desktop responsiveness esp
when firefox is chewing a lot.
dma-buf:
- fix memory leak
core:
- shmem object mmap fix.
ttm:
- Fix fence leak in ttm_buffer_object_transfer().
amdgpu:
- Gfx reset fix for gfx9, 10
- Fix for gfx10
- DP MST fix
- DCC fix
- Renoir power fixes
- Navi power fix
i915:
- Break up long lists of object reclaim with cond_resched()
- PSR probe fix
- TGL workarounds
- Selftest return value fix
- Drop timeline mutex while waiting for retirement
- Wait for OA configuration completion before writes to OA buffer
virtio:
- Fix resource id creation race in virtio.
- mmap fixes
sun4i:
- Fixes for sun4i VI layer format support.
kirin:
- kirin: Revert "Fix for hikey620 display offset problem"
exynos:
- fix a kernel oops problem in case that driver is loaded as module.
- fix a regulator warning issue when I2C DDC adapter cannot be gathered.
- print out an error message only in error case excepting -EPROBE_DEFER.
mediatek:
- overlay, cursor and gce fixes"
`
* tag 'drm-fixes-2020-03-06' of git://anongit.freedesktop.org/drm/drm: (38 commits)
drm/amdgpu/display: navi1x copy dcn watermark clock settings to smu resume from s3 (v2)
drm/amd/powerplay: map mclk to fclk for COMBINATIONAL_BYPASS case
drm/amd/powerplay: fix pre-check condition for setting clock range
drm/amd/display: fix dcc swath size calculations on dcn1
drm/amd/display: Clear link settings on MST disable connector
drm/amdgpu: disable 3D pipe 1 on Navi1x
drm/amdgpu: clean wptr on wb when gpu recovery
drm: kirin: Revert "Fix for hikey620 display offset problem"
drm/i915/gt: Drop the timeline->mutex as we wait for retirement
drm/i915/perf: Reintroduce wait on OA configuration completion
drm/sun4i: Fix DE2 VI layer format support
drm/sun4i: Add separate DE3 VI layer formats
drm/sun4i: de2/de3: Remove unsupported VI layer formats
drm/i915/selftests: Fix return in assert_mmap_offset()
drm/i915: Protect i915_request_await_start from early waits
drm/i915/tgl: Add Wa_1608008084
drm/i915/tgl: Add Wa_22010178259:tgl
drm/i915: Program MBUS with rmw during initialization
drm/i915/psr: Force PSR probe only after full initialization
drm/i915/gem: Break up long lists of object reclaim
...
Now smp_call_function_single_async() provides the protection that
we'll return with -EBUSY if the csd object is still pending, then we
don't need the rq.hrtick_csd_pending any more.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20191216213125.9536-4-peterx@redhat.com
Now smp_call_function_single_async() provides the protection that
we'll return with -EBUSY if the csd object is still pending, then we
don't need the tick_broadcast_count counter any more.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20191216213125.9536-3-peterx@redhat.com
Previously we will raise an warning if we want to insert a csd object
which is with the LOCK flag set, and if it happens we'll also wait for
the lock to be released. However, this operation does not match
perfectly with how the function is named - the name with "_async"
suffix hints that this function should not block, while we will.
This patch changed this behavior by simply return -EBUSY instead of
waiting, at the meantime we allow this operation to happen without
warning the user to change this into a feature when the caller wants
to "insert a csd object, if it's there, just wait for that one".
This is pretty safe because in flush_smp_call_function_queue() for
async csd objects (where csd->flags&SYNC is zero) we'll first do the
unlock then we call the csd->func(). So if we see the csd->flags&LOCK
is true in smp_call_function_single_async(), then it's guaranteed that
csd->func() will be called after this smp_call_function_single_async()
returns -EBUSY.
Update the comment of the function too to refect this.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20191216213125.9536-2-peterx@redhat.com
Remove the dependency with ARCH_SPRD from sprd serial/console Kconfig-s,
since we want them can be built-in when ARCH_SPRD is set as 'm'.
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20200305103228.9686-2-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The default value of Kconfig for almost all sprd drivers are the same with
ARCH_SPRD, making these drivers built as modules as default would be easier
if we can set ARCH_SPRD as 'm', so this patch change ARCH_SPRD to tristate.
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20200305103228.9686-1-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ->setup() callback is mandatory for the devices.
Provide it for Elkhart Lake UART ports.
Note, for time being it's empty, but in the future it might require
an additional configuration such as DMA.
Reported-by: Raymond Tan <raymond.tan@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200305130822.36850-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MTK uart design no need to control uart clock,
so we just control bus clock in runtime function.
Add uart clock used count to avoid repeatedly switching the clock.
Signed-off-by: Changqi Hu <changqi.hu@mediatek.com>
Link: https://lore.kernel.org/r/1582707225-26815-1-git-send-email-changqi.hu@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The peripheral has support for inverting its input and/or output
signals. This is useful if the hardware flips polarity of the
peripheral's signal, such as swapped +/- pins on an RS-422 transceiver,
or an inverting level shifter. Add support for these control registers
via the device tree binding.
As part of this change, make the writes of the various registers more
uniform by moving the UCR3 block up near the other registers' blocks,
since the INVT bit must be set before enabling the peripheral.
Signed-off-by: George Hilliard <ghilliard@kopismobile.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20200226222319.18383-3-ghilliard@kopismobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a description for the new fsl,inverted-tx and fsl,inverted-rx
options for the i.MX UART peripheral.
Signed-off-by: George Hilliard <ghilliard@kopismobile.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200226222319.18383-2-ghilliard@kopismobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Emulate half-duplex operation and use mctrl_gpio to add support for
RS485 tranceiver with transmit/receive switch hooked to RTS GPIO line.
This is needed to make use of the RS485 port found on Teltonika RUT955.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Link: https://lore.kernel.org/r/20200221212331.GA21467@makrotopia.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
