Linux kernel
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From time to time DMA completion can come in the middle of DMA shutdown:
<process ctx>: <IRQ>:
lpuart32_shutdown()
lpuart_dma_shutdown()
del_timer_sync()
lpuart_dma_rx_complete()
lpuart_copy_rx_to_tty()
mod_timer()
lpuart_dma_rx_free()
When the timer fires a bit later, sport->dma_rx_desc is NULL:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004
pc : lpuart_copy_rx_to_tty+0xcc/0x5bc
lr : lpuart_timer_func+0x1c/0x2c
Call trace:
lpuart_copy_rx_to_tty
lpuart_timer_func
call_timer_fn
__run_timers.part.0
run_timer_softirq
__do_softirq
__irq_exit_rcu
irq_exit
handle_domain_irq
gic_handle_irq
call_on_irq_stack
do_interrupt_handler
...
To fix this fold del_timer_sync() into lpuart_dma_rx_free() after
dmaengine_terminate_sync() to make sure timer will not be re-started in
lpuart_copy_rx_to_tty() <= lpuart_dma_rx_complete().
Fixes: 4a8588a1cf86 ("serial: fsl_lpuart: delete timer on shutdown")
Cc: stable <stable@kernel.org>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Link: https://lore.kernel.org/r/20230309134302.74940-2-alexander.sverdlin@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 32bb477fa7bf ("serial: 8250_pci1xxxx: Add driver for quad-uart
support") made the SERIAL_8250_PCI1XXXX driver enabled when SERIAL_8250
is enabled, disable it as this driver does not need to be enabled by
default
Fixes: 32bb477fa7bf ("serial: 8250_pci1xxxx: Add driver for quad-uart support")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/lkml/CAHk-=whhFCeeuo6vTEmNSx6S-KKkugxgzN_W5Z6v-9yH9gc3Zw@mail.gmail.com/
Signed-off-by: Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230305145124.13444-1-kumaravel.thiagarajan@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The 8250 handle_irq callback is not just called from the interrupt
handler but also from a timer callback when polling (e.g. for ports
without an interrupt line). Consequently the callback must explicitly
disable interrupts to avoid a potential deadlock with another interrupt
in polled mode.
Fix up the two paths in the freescale callback that failed to re-enable
interrupts when polling.
Fixes: 853a9ae29e97 ("serial: 8250: fix handle_irq locking")
Cc: stable@vger.kernel.org # 5.13
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/r/Y/xYzqp4ogmOF5t0@kili
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230227085046.24282-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As per HW manual for EMEV2 "R19UH0040EJ0400 Rev.4.00", the UART
IP found on EMMA mobile SoC is Register-compatible with the
general-purpose 16750 UART chip. Fix UART port type as 16750 and
enable 64-bytes fifo support.
Fixes: 22886ee96895 ("serial8250-em: Emma Mobile UART driver V2")
Cc: stable@vger.kernel.org
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20230227114152.22265-2-biju.das.jz@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
REGMAP is a hidden (not user visible) symbol. Users cannot set it
directly thru "make *config", so drivers should select it instead of
depending on it if they need it.
Consistently using "select" or "depends on" can also help reduce
Kconfig circular dependency issues.
Therefore, change the use of "depends on REGMAP" to "select REGMAP".
Fixes: 8d310c9107a2 ("drivers/tty/serial/8250: Make Aspeed VUART SIRQ polarity configurable")
Cc: stable <stable@kernel.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Oskar Senft <osk@google.com>
Cc: linux-serial@vger.kernel.org
Link: https://lore.kernel.org/r/20230226053953.4681-9-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
According to LPUART RM, Transmission Complete Flag becomes 0 if queuing
a break character by writing 1 to CTRL[SBK], so here need to skip
waiting for transmission complete when UARTCTRL_SBK is asserted,
otherwise the kernel may stuck here.
And actually set_termios() adds transmission completion waiting to avoid
data loss or data breakage when changing the baud rate, but we don't
need to worry about this when queuing break characters.
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20230223093941.31790-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 5779a072c248db7a40cfd0f5ea958097fd1d9a30.
This results in a link error of
ld: drivers/tty/serial/earlycon.o: in function `parse_options':
drivers/tty/serial/earlycon.c:99: undefined reference to `uart_parse_earlycon'
When the config is in this state
CONFIG_SERIAL_CORE=m
CONFIG_SERIAL_CORE_CONSOLE=y
CONFIG_SERIAL_EARLYCON=y
CONFIG_SERIAL_FSL_LPUART=m
CONFIG_SERIAL_FSL_LPUART_CONSOLE=y
Fixes: 5779a072c248 ("tty: serial: fsl_lpuart: adjust SERIAL_FSL_LPUART_CONSOLE config dependency")
Cc: stable <stable@kernel.org>
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230226173846.236691-1-trix@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit aa47a7c215e7 ("lib/cpumask: deprecate nr_cpumask_bits") resulted
in the cpumask operations potentially becoming hugely less efficient,
because suddenly the cpumask was always considered to be variable-sized.
The optimization was then later added back in a limited form by commit
6f9c07be9d02 ("lib/cpumask: add FORCE_NR_CPUS config option"), but that
FORCE_NR_CPUS option is not useful in a generic kernel and more of a
special case for embedded situations with fixed hardware.
Instead, just re-introduce the optimization, with some changes.
Instead of depending on CPUMASK_OFFSTACK being false, and then always
using the full constant cpumask width, this introduces three different
cpumask "sizes":
- the exact size (nr_cpumask_bits) remains identical to nr_cpu_ids.
This is used for situations where we should use the exact size.
- the "small" size (small_cpumask_bits) is the NR_CPUS constant if it
fits in a single word and the bitmap operations thus end up able
to trigger the "small_const_nbits()" optimizations.
This is used for the operations that have optimized single-word
cases that get inlined, notably the bit find and scanning functions.
- the "large" size (large_cpumask_bits) is the NR_CPUS constant if it
is an sufficiently small constant that makes simple "copy" and
"clear" operations more efficient.
This is arbitrarily set at four words or less.
As a an example of this situation, without this fixed size optimization,
cpumask_clear() will generate code like
movl nr_cpu_ids(%rip), %edx
addq $63, %rdx
shrq $3, %rdx
andl $-8, %edx
callq memset@PLT
on x86-64, because it would calculate the "exact" number of longwords
that need to be cleared.
In contrast, with this patch, using a MAX_CPU of 64 (which is quite a
reasonable value to use), the above becomes a single
movq $0,cpumask
instruction instead, because instead of caring to figure out exactly how
many CPU's the system has, it just knows that the cpumask will be a
single word and can just clear it all.
Note that this does end up tightening the rules a bit from the original
version in another way: operations that set bits in the cpumask are now
limited to the actual nr_cpu_ids limit, whereas we used to do the
nr_cpumask_bits thing almost everywhere in the cpumask code.
But if you just clear bits, or scan for bits, we can use the simpler
compile-time constants.
In the process, remove 'cpumask_complement()' and 'for_each_cpu_not()'
which were not useful, and which fundamentally have to be limited to
'nr_cpu_ids'. Better remove them now than have somebody introduce use
of them later.
Of course, on x86-64 with MAXSMP there is no sane small compile-time
constant for the cpumask sizes, and we end up using the actual CPU bits,
and will generate the above kind of horrors regardless. Please don't
use MAXSMP unless you really expect to have machines with thousands of
cores.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull crypto fix from Herbert Xu:
"Fix a regression in the caam driver"
* tag 'v6.3-p2' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: caam - Fix edesc/iv ordering mixup
Pull x86 updates from Thomas Gleixner:
"A small set of updates for x86:
- Return -EIO instead of success when the certificate buffer for SEV
guests is not large enough
- Allow STIPB to be enabled with legacy IBSR. Legacy IBRS is cleared
on return to userspace for performance reasons, but the leaves user
space vulnerable to cross-thread attacks which STIBP prevents.
Update the documentation accordingly"
* tag 'x86-urgent-2023-03-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
virt/sev-guest: Return -EIO if certificate buffer is not large enough
Documentation/hw-vuln: Document the interaction between IBRS and STIBP
x86/speculation: Allow enabling STIBP with legacy IBRS
The attempt to add DMA alignment padding by moving IV to the front
of edesc was completely broken as it didn't change the places where
edesc was freed.
It's also wrong as the IV may still share a cache-line with the
edesc.
Fix this by restoring the original layout and simply reserving
enough memmory so that the IV is on a DMA cache-line by itself.
Reported-by: Meenakshi Aggarwal <meenakshi.aggarwal@nxp.com>
Fixes: 199354d7fb6e ("crypto: caam - Remove GFP_DMA and add DMA alignment padding")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull irq updates from Thomas Gleixner:
"A set of updates for the interrupt susbsystem:
- Prevent possible NULL pointer derefences in
irq_data_get_affinity_mask() and irq_domain_create_hierarchy()
- Take the per device MSI lock before invoking code which relies on
it being hold
- Make sure that MSI descriptors are unreferenced before freeing
them. This was overlooked when the platform MSI code was converted
to use core infrastructure and results in a fals positive warning
- Remove dead code in the MSI subsystem
- Clarify the documentation for pci_msix_free_irq()
- More kobj_type constification"
* tag 'irq-urgent-2023-03-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/msi, platform-msi: Ensure that MSI descriptors are unreferenced
genirq/msi: Drop dead domain name assignment
irqdomain: Add missing NULL pointer check in irq_domain_create_hierarchy()
genirq/irqdesc: Make kobj_type structures constant
PCI/MSI: Clarify usage of pci_msix_free_irq()
genirq/msi: Take the per-device MSI lock before validating the control structure
genirq/ipi: Fix NULL pointer deref in irq_data_get_affinity_mask()
Commit
47894e0fa6a5 ("virt/sev-guest: Prevent IV reuse in the SNP guest driver")
changed the behavior associated with the return value when the caller
does not supply a large enough certificate buffer. Prior to the commit a
value of -EIO was returned. Now, 0 is returned. This breaks the
established ABI with the user.
Change the code to detect the buffer size error and return -EIO.
Fixes: 47894e0fa6a5 ("virt/sev-guest: Prevent IV reuse in the SNP guest driver")
Reported-by: Larry Dewey <larry.dewey@amd.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Larry Dewey <larry.dewey@amd.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/2afbcae6daf13f7ad5a4296692e0a0fe1bc1e4ee.1677083979.git.thomas.lendacky@amd.com
vpbroadcastb and vpbroadcastd are not AVX instructions.
But the aria-avx assembly code contains these instructions.
So, kernel panic will occur if the aria-avx works on AVX2 unsupported
CPU.
vbroadcastss, and vpshufb are used to avoid using vpbroadcastb in it.
Unfortunately, this change reduces performance by about 5%.
Also, vpbroadcastd is simply replaced by vmovdqa in it.
Fixes: ba3579e6e45c ("crypto: aria-avx - add AES-NI/AVX/x86_64/GFNI assembler implementation of aria cipher")
Reported-by: Herbert Xu <herbert@gondor.apana.org.au>
Reported-by: Erhard F. <erhard_f@mailbox.org>
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>