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Linux kernel
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Pull x86 fixes from Borislav Petkov:
- Prevent potential undefined behavior due to shifting pkey constants
into the sign bit
- Move the EFI memory reservation code *after* the efi= cmdline parsing
has happened
- Revert two commits which turned out to be the wrong direction to
chase when accommodating early memblock reservations consolidation
and command line parameters parsing
* tag 'x86_urgent_for_v5.16_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/pkey: Fix undefined behaviour with PKRU_WD_BIT
x86/boot: Move EFI range reservation after cmdline parsing
Revert "x86/boot: Pull up cmdline preparation and early param parsing"
Revert "x86/boot: Mark prepare_command_line() __init"
Pull objtool fixes from Borislav Petkov:
- Prevent clang from reordering the reachable annotation in
an inline asm statement without inputs
- Fix objtool builds on non-glibc systems due to undefined
__always_inline
* tag 'objtool_urgent_for_v5.16_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
compiler.h: Fix annotation macro misplacement with Clang
uapi: Fix undefined __always_inline on non-glibc systems
Both __pkru_allows_write() and arch_set_user_pkey_access() shift
PKRU_WD_BIT (a signed constant) by up to 30 bits, hitting the
sign bit.
Use unsigned constants instead.
Clearly pkey 15 has not been used in combination with UBSAN yet.
Noticed by code inspection only. I can't actually provoke the
compiler into generating incorrect logic as far as this shift is
concerned.
[
dhansen: add stable@ tag, plus minor changelog massaging,
For anyone doing backports, these #defines were in
arch/x86/include/asm/pgtable.h before 784a46618f6.
]
Fixes: 33a709b25a76 ("mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20211216000856.4480-1-andrew.cooper3@citrix.com
Pull pin control fixes from Linus Walleij:
"Some hopefully final pin control fixes for the v5.16 kernel:
- Fix an out-of-bounds bug in the Mediatek driver
- Fix an init order bug in the Broadcom BCM2835 driver
- Fix a GPIO offset bug in the STM32 driver"
* tag 'pinctrl-v5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: stm32: consider the GPIO offset to expose all the GPIO lines
pinctrl: bcm2835: Change init order for gpio hogs
pinctrl: mediatek: fix global-out-of-bounds issue
When building with Clang and CONFIG_TRACE_BRANCH_PROFILING, there are a
lot of unreachable warnings, like:
arch/x86/kernel/traps.o: warning: objtool: handle_xfd_event()+0x134: unreachable instruction
Without an input to the inline asm, 'volatile' is ignored for some
reason and Clang feels free to move the reachable() annotation away from
its intended location.
Fix that by re-adding the counter value to the inputs.
Fixes: f1069a8756b9 ("compiler.h: Avoid using inline asm operand modifiers")
Fixes: c199f64ff93c ("instrumentation.h: Avoid using inline asm operand modifiers")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/0417e96909b97a406323409210de7bf13df0b170.1636410380.git.jpoimboe@redhat.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: x86@kernel.org
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Miroslav Benes <mbenes@suse.cz>
The memory reservation in arch/x86/platform/efi/efi.c depends on at
least two command line parameters. Put it back later in the boot process
and move efi_memblock_x86_reserve_range() out of early_memory_reserve().
An attempt to fix this was done in
8d48bf8206f7 ("x86/boot: Pull up cmdline preparation and early param parsing")
but that caused other troubles so it got reverted.
The bug this is addressing is:
Dan reports that Anjaneya Chagam can no longer use the efi=nosoftreserve
kernel command line parameter to suppress "soft reservation" behavior.
This is due to the fact that the following call-chain happens at boot:
early_reserve_memory
|-> efi_memblock_x86_reserve_range
|-> efi_fake_memmap_early
which does
if (!efi_soft_reserve_enabled())
return;
and that would have set EFI_MEM_NO_SOFT_RESERVE after having parsed
"nosoftreserve".
However, parse_early_param() gets called *after* it, leading to the boot
cmdline not being taken into account.
See also https://lore.kernel.org/r/e8dd8993c38702ee6dd73b3c11f158617e665607.camel@intel.com
[ bp: Turn into a proper patch. ]
Signed-off-by: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211213112757.2612-4-bp@alien8.de
Pull hwmon fixes from Guenter Roeck:
"A couple of lm90 driver fixes. None of them are critical, but they
should nevertheless be fixed"
* tag 'hwmon-for-v5.16-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (lm90) Do not report 'busy' status bit as alarm
hwmom: (lm90) Fix citical alarm status for MAX6680/MAX6681
hwmon: (lm90) Drop critical attribute support for MAX6654
hwmon: (lm90) Prevent integer overflow/underflow in hysteresis calculations
hwmon: (lm90) Fix usage of CONFIG2 register in detect function
Consider the GPIO controller offset (from "gpio-ranges") to compute the
maximum GPIO line number.
This fixes an issue where gpio-ranges uses a non-null offset.
e.g.: gpio-ranges = <&pinctrl 6 86 10>
In that case the last valid GPIO line is not 9 but 15 (6 + 10 - 1)
Cc: stable@vger.kernel.org
Fixes: 67e2996f72c7 ("pinctrl: stm32: fix the reported number of GPIO lines per bank")
Reported-by: Christoph Fritz <chf.fritz@googlemail.com>
Signed-off-by: Fabien Dessenne <fabien.dessenne@foss.st.com>
Link: https://lore.kernel.org/r/20211215095808.621716-1-fabien.dessenne@foss.st.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This macro is defined by glibc itself, which makes the issue go unnoticed on
those systems. On non-glibc systems it causes build failures on several
utilities and libraries, like bpftool and objtool.
Fixes: 1d509f2a6ebc ("x86/insn: Support big endian cross-compiles")
Fixes: 2d7ce0e8a704 ("tools/virtio: more stubs")
Fixes: 3fb321fde22d ("selftests/net: ipv6 flowlabel")
Fixes: 50b3ed57dee9 ("selftests/bpf: test bpf flow dissection")
Fixes: 9cacf81f8161 ("bpf: Remove extra lock_sock for TCP_ZEROCOPY_RECEIVE")
Fixes: a4b2061242ec ("tools include uapi: Grab a copy of linux/in.h")
Fixes: b12d6ec09730 ("bpf: btf: add btf print functionality")
Fixes: c0dd967818a2 ("tools, include: Grab a copy of linux/erspan.h")
Fixes: c4b6014e8bb0 ("tools: Add copy of perf_event.h to tools/include/linux/")
Signed-off-by: Ismael Luceno <ismael@iodev.co.uk>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20211115134647.1921-1-ismael@iodev.co.uk
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
This reverts commit 8d48bf8206f77aa8687f0e241e901e5197e52423.
It turned out to be a bad idea as it broke supplying mem= cmdline
parameters due to parse_memopt() requiring preparatory work like setting
up the e820 table in e820__memory_setup() in order to be able to exclude
the range specified by mem=.
Pulling that up would've broken Xen PV again, see threads at
https://lkml.kernel.org/r/20210920120421.29276-1-jgross@suse.com
due to xen_memory_setup() needing the first reservations in
early_reserve_memory() - kernel and initrd - to have happened already.
This could be fixed again by having Xen do those reservations itself...
Long story short, revert this and do a simpler fix in a later patch.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211213112757.2612-3-bp@alien8.de
Pull input fixes from Dmitry Torokhov:
"A few small updates to drivers.
Of note we are now deferring probes of i8042 on some Asus devices as
the controller is not ready to respond to queries first time around
when the driver is compiled into the kernel"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: elants_i2c - do not check Remark ID on eKTH3900/eKTH5312
Input: atmel_mxt_ts - fix double free in mxt_read_info_block
Input: goodix - fix memory leak in goodix_firmware_upload
Input: goodix - add id->model mapping for the "9111" model
Input: goodix - try not to touch the reset-pin on x86/ACPI devices
Input: i8042 - enable deferred probe quirk for ASUS UM325UA
Input: elantech - fix stack out of bound access in elantech_change_report_id()
Input: iqs626a - prohibit inlining of channel parsing functions
Input: i8042 - add deferred probe support
Bit 7 of the status register indicates that the chip is busy
doing a conversion. It does not indicate an alarm status.
Stop reporting it as alarm status bit.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
...and gpio-ranges
pinctrl-bcm2835 is a combined pinctrl/gpio driver. Currently the gpio
side is registered first, but this breaks gpio hogs (which are
configured during gpiochip_add_data). Part of the hog initialisation
is a call to pinctrl_gpio_request, and since the pinctrl driver hasn't
yet been registered this results in an -EPROBE_DEFER from which it can
never recover.
Change the initialisation sequence to register the pinctrl driver
first.
This also solves a similar problem with the gpio-ranges property, which
is required in order for released pins to be returned to inputs.
Fixes: 73345a18d464b ("pinctrl: bcm2835: Pass irqchip when adding gpiochip")
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20211206092237.4105895-2-phil@raspberrypi.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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