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Linux kernel
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Currently we emit the REQUESTED line state event after the line is
requested but before the flags are configured. This is obviously wrong
as we want to pass the updated lineinfo to user-space together with the
event.
Since the flags can be configured in different ways depending on how the
line is being requested - we need to call the notifier chain in different
places separately.
Fixes: 51c1064e82e7 ("gpiolib: add new ioctl() for monitoring changes in line info")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
The commit 7ecced0934e5 ("gpio: exar: add a check for the return value
of ida_simple_get fails") added a goto jump to the common error
handler for ida_simple_get() error, but this is wrong in two ways:
it doesn't set the proper return code and, more badly, it invokes
ida_simple_remove() with a negative index that shall lead to a kernel
panic via BUG_ON().
This patch addresses those two issues.
Fixes: 7ecced0934e5 ("gpio: exar: add a check for the return value of ida_simple_get fails")
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
The PWM iomem resource is optional and its presence indicates whether
the GPIO chip has a PWM or not, which is why mvebu_pwm_probe() returned
successfully when the PWM resource was not present. With f51b18d92b66
the driver switched to devm_platform_ioremap_resource_byname() and
its error return is propagated to the caller, so now a missing PWM resource
leads to a probe error in the driver.
To fix this explicitly test for the presence of the PWM resource and
return successfully when it's not there. Do this check before the check
for the clock is done (which GPIO chips without a PWM do not have). Also
move the existing comment why the PWM resource is optional up to the
actual check.
Fixes: f51b18d92b66 ("gpio: mvebu: use devm_platform_ioremap_resource_byname()")
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
We must not call pinctrl_gpio_can_use_line() with the gpio_lock taken
as it takes a mutex internally. Let's move the call before taking the
spinlock and store the return value.
This isn't perfect - there's a moment between calling
pinctrl_gpio_can_use_line() and taking the spinlock where the situation
can change but it isn't a regression either: previously this part wasn't
protected at all and it only affects the information user-space is
seeing.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: d2ac25798208 ("gpiolib: provide a dedicated function for setting lineinfo")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
This makes the new ioctl() a bit more robust - we now check if a line
is already being watched and return -EBUSY if the user-space tries to
start watching it again. Same for unwatch - return -EBUSY if user-space
tries to unwatch a line that's not being watched.
Fixes: 51c1064e82e7 ("gpiolib: add new ioctl() for monitoring changes in line info")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
pca953x_gpio_set_config is setup to support pull-up/down
bias. Currently the driver uses a variable called 'config' to
determine which options to use. Unfortunately, this is incorrect.
This patch uses function pinconf_to_config_param(config), which
converts this 'config' parameter back to pinconfig to determine
which option to use.
Fixes: 15add06841a3 ("gpio: pca953x: add ->set_config implementation")
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
When remapping a mapping where a portion of a VMA is remapped
into another portion of the VMA it can cause the VMA to become
split. During the copy_vma operation the VMA can actually
be remerged if it's an anonymous VMA whose pages have not yet
been faulted. This isn't normally a problem because at the end
of the remap the original portion is unmapped causing it to
become split again.
However, MREMAP_DONTUNMAP leaves that original portion in place which
means that the VMA which was split and then remerged is not actually
split at the end of the mremap. This patch fixes a bug where
we don't detect that the VMAs got remerged and we end up
putting back VM_ACCOUNT on the next mapping which is completely
unreleated. When that next mapping is unmapped it results in
incorrectly unaccounting for the memory which was never accounted,
and eventually we will underflow on the memory comittment.
There is also another issue which is similar, we're currently
accouting for the number of pages in the new_vma but that's wrong.
We need to account for the length of the remap operation as that's
all that is being added. If there was a mapping already at that
location its comittment would have been adjusted as part of
the munmap at the start of the mremap.
A really simple repro can be seen in:
https://gist.github.com/bgaff/e101ce99da7d9a8c60acc641d07f312c
Fixes: e346b3813067 ("mm/mremap: add MREMAP_DONTUNMAP to mremap()")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Brian Geffon <bgeffon@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull clk fixes from Stephen Boyd:
"Two build fixes for a couple clk drivers and a fix for the Unisoc
serial clk where we want to keep it on for earlycon"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: sprd: don't gate uart console clock
clk: mmp2: fix link error without mmp2
clk: asm9260: fix __clk_hw_register_fixed_rate_with_accuracy typo
Pull x86 and objtool fixes from Thomas Gleixner:
"A set of fixes for x86 and objtool:
objtool:
- Ignore the double UD2 which is emitted in BUG() when
CONFIG_UBSAN_TRAP is enabled.
- Support clang non-section symbols in objtool ORC dump
- Fix switch table detection in .text.unlikely
- Make the BP scratch register warning more robust.
x86:
- Increase microcode maximum patch size for AMD to cope with new CPUs
which have a larger patch size.
- Fix a crash in the resource control filesystem when the removal of
the default resource group is attempted.
- Preserve Code and Data Prioritization enabled state accross CPU
hotplug.
- Update split lock cpu matching to use the new X86_MATCH macros.
- Change the split lock enumeration as Intel finaly decided that the
IA32_CORE_CAPABILITIES bits are not architectural contrary to what
the SDM claims. !@#%$^!
- Add Tremont CPU models to the split lock detection cpu match.
- Add a missing static attribute to make sparse happy"
* tag 'x86-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/split_lock: Add Tremont family CPU models
x86/split_lock: Bits in IA32_CORE_CAPABILITIES are not architectural
x86/resctrl: Preserve CDP enable over CPU hotplug
x86/resctrl: Fix invalid attempt at removing the default resource group
x86/split_lock: Update to use X86_MATCH_INTEL_FAM6_MODEL()
x86/umip: Make umip_insns static
x86/microcode/AMD: Increase microcode PATCH_MAX_SIZE
objtool: Make BP scratch register warning more robust
objtool: Fix switch table detection in .text.unlikely
objtool: Support Clang non-section symbols in ORC generation
objtool: Support Clang non-section symbols in ORC dump
objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings
Don't gate uart1_eb which provides console clock, gating that clock would
make serial stop working if serial driver didn't enable that explicitly.
Fixes: 0e4b8a2349f3 ("clk: sprd: add clocks support for SC9863A")
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lkml.kernel.org/r/20200408020234.31764-1-zhang.lyra@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull time namespace fix from Thomas Gleixner:
"An update for the proc interface of time namespaces: Use symbolic
names instead of clockid numbers. The usability nuisance of numbers
was noticed by Michael when polishing the man page"
* tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets
Tremont CPUs support IA32_CORE_CAPABILITIES bits to indicate whether
specific SKUs have support for split lock detection.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200416205754.21177-4-tony.luck@intel.com
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