Commit a6845e1e1b ("serial: core: Consider rs485 settings to drive
RTS") sought to deassert RTS when opening an rs485-enabled uart port.
That way, the transceiver does not occupy the bus until it transmits
data.
Unfortunately, the commit mixed up the logic and *asserted* RTS instead
of *deasserting* it:
The commit amended uart_port_dtr_rts(), which raises DTR and RTS when
opening an rs232 port. "Raising" actually means lowering the signal
that's coming out of the uart, because an rs232 transceiver not only
changes a signal's voltage level, it also *inverts* the signal. See
the simplified schematic in the MAX232 datasheet for an example:
https://www.ti.com/lit/ds/symlink/max232.pdf
So, to raise RTS on an rs232 port, TIOCM_RTS is *set* in port->mctrl
and that results in the signal being driven low.
In contrast to rs232, the signal level for rs485 Transmit Enable is the
identity, not the inversion: If the transceiver expects a "high" RTS
signal for Transmit Enable, the signal coming out of the uart must also
be high, so TIOCM_RTS must be *cleared* in port->mctrl.
The commit did the exact opposite, but it's easy to see why given the
confusing semantics of rs232 and rs485. Fix it.
Fixes: a6845e1e1b ("serial: core: Consider rs485 settings to drive RTS")
Cc: stable@vger.kernel.org # v4.14+
Cc: Rafael Gago Castano <rgc@hms.se>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Su Bao Cheng <baocheng.su@siemens.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/9395767847833f2f3193c49cde38501eeb3b5669.1639821059.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Note: I am using a small test app + driver located at [0] for the
problem description. serco is a driver whose write function dispatches
to the serial controller. sertest is a user-mode app that writes n bytes
to the serial console using the serco driver.
While investigating a bug in the RHEL kernel, I noticed that the serial
console throughput is way below the configured speed of 115200 bps in
a HP Proliant DL380 Gen9. I was expecting something above 10KB/s, but
I got 2.5KB/s.
$ time ./sertest -n 2500 /tmp/serco
real 0m0.997s
user 0m0.000s
sys 0m0.997s
With the help of the function tracer, I then noticed the serial
controller was taking around 410us seconds to dispatch one single byte:
$ trace-cmd record -p function_graph -g serial8250_console_write \
./sertest -n 1 /tmp/serco
$ trace-cmd report
| serial8250_console_write() {
0.384 us | _raw_spin_lock_irqsave();
1.836 us | io_serial_in();
1.667 us | io_serial_out();
| uart_console_write() {
| serial8250_console_putchar() {
| wait_for_xmitr() {
1.870 us | io_serial_in();
2.238 us | }
1.737 us | io_serial_out();
4.318 us | }
4.675 us | }
| wait_for_xmitr() {
1.635 us | io_serial_in();
| __const_udelay() {
1.125 us | delay_tsc();
1.429 us | }
...
...
...
1.683 us | io_serial_in();
| __const_udelay() {
1.248 us | delay_tsc();
1.486 us | }
1.671 us | io_serial_in();
411.342 us | }
In another machine, I measured a throughput of 11.5KB/s, with the serial
controller taking between 80-90us to send each byte. That matches the
expected throughput for a configuration of 115200 bps.
This patch changes the serial8250_console_write to use the 16550 fifo
if available. In my benchmarks I got around 25% improvement in the slow
machine, and no performance penalty in the fast machine.
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Link: https://lore.kernel.org/r/20211222112831.1968392-2-wander@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since b9e851cd4a ("tty: n_gsm: Add some instructions and code for requester") which
introduced a warning:
linux/Documentation/driver-api/serial/n_gsm.rst:23: WARNING: Definition list ends without a blank line; unexpected unindent.
linux/Documentation/driver-api/serial/n_gsm.rst💯 WARNING: Definition list ends without a blank line; unexpected unindent.
linux/Documentation/driver-api/serial/n_gsm.rst:115: WARNING: Inline emphasis start-string without end-string.
linux/Documentation/driver-api/serial/n_gsm.rst:118: WARNING: Inline emphasis start-string without end-string.
linux/Documentation/driver-api/serial/n_gsm.rst:120: WARNING: Inline emphasis start-string without end-string.
linux/Documentation/driver-api/serial/n_gsm.rst:122: WARNING: Inline emphasis start-string without end-string.
linux/Documentation/driver-api/serial/n_gsm.rst:125: WARNING: Inline emphasis start-string without end-string.
linux/Documentation/driver-api/serial/n_gsm.rst:139: WARNING: Inline emphasis start-string without end-string.
A paragraph consisting of two colons ("::") signifies that the following text block(s) comprise a literal block.
Add soome blank lines.
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Link: https://lore.kernel.org/r/20211209092439.562433-1-siyanteng@loongson.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the "ctrl+alt+Fn" key combination to switch the system from tty to
desktop or switch the system from desktop to tty. After the switch is
completed, it is found that the state of the keyboard lock is
inconsistent with the state of the keyboard Led light.The reasons are
as follows:
* The desktop environment (Xorg and other services) is bound to a tty
(assuming it is tty1), and the kb->kbdmode attribute value of tty1
will be set to VC_OFF. According to the current code logic, in the
desktop environment, the values of ledstate and kb->ledflagstate
of tty1 will not be modified anymore, so they are always 0.
* When switching between each tty, the final value of ledstate set by
the previous tty is compared with the kb->ledflagstate value of the
current tty to determine whether to set the state of the keyboard
light. The process of switching between desktop and tty is also the
process of switching between tty1 and other ttys. There are two
situations:
- (1) In the desktop environment, tty1 will not set the ledstate,
which will cause when switching from the desktop to other ttys,
if the desktop lights up the keyboard's led, after the switch is
completed, the keyboard's led light will always be on;
- (2) When switching from another tty to the desktop, this
mechanism will trigger tty1 to set the led state. If other tty
lights up the led of the keyboard before switching to the desktop,
the led will be forcibly turned off. This situation should
be avoided.
* The current patch is to solve these problems: When VT is switched,
the keyboard led needs to be set once.Ensure that after the
switch is completed, the state of the keyboard LED is consistent
with the state of the keyboard lock.
Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: lianzhi chang <changlianzhi@uniontech.com>
Link: https://lore.kernel.org/r/20211215125125.10554-1-changlianzhi@uniontech.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On modern Exynos SoCs (like Exynos850) the UART can be implemented as a
part of USI IP-core. In such case, USI driver is used to initialize USI
registers, and it also calls of_platform_populate() to instantiate all
sub-nodes (e.g. serial node) of USI node. When serial driver is
built-in, but USI driver is a module, and CONFIG_SERIAL_SAMSUNG_CONSOLE
is enabled, next call chain will happen when loading USI module from
user space:
usi_init
v
usi_probe
v
of_platform_populate
v
s3c24xx_serial_probe
v
uart_add_one_port
v
uart_configure_port
v
register_console
v
try_enable_new_console
v
s3c24xx_serial_console_setup
But because the serial driver is built-in, and
s3c24xx_serial_console_setup() is marked with __init keyword, that
symbol will discarded and long gone by that time already, causing failed
paging request.
That happens during the next config combination:
EXYNOS_USI=m
SERIAL_SAMSUNG=y
SERIAL_SAMSUNG_CONSOLE=y
That config should be completely possible, so rather than limiting
SERIAL_SAMSUNG choice to "m" only when USI=m, remove __init keyword for
all affected functions.
Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20211204195757.8600-6-semen.protsenko@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull kvm fixes from Paolo Bonzini:
"Two small fixes, one of which was being worked around in selftests"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: Retry page fault if MMU reload is pending and root has no sp
KVM: selftests: vmx_pmu_msrs_test: Drop tests mangling guest visible CPUIDs
KVM: x86: Drop guest CPUID check for host initiated writes to MSR_IA32_PERF_CAPABILITIES
Pull block revert from Jens Axboe:
"It turns out that the fix for not hammering on the delayed work timer
too much caused a performance regression for BFQ, so let's revert the
change for now.
I've got some ideas on how to fix it appropriately, but they should
wait for 5.17"
* tag 'block-5.16-2021-12-19' of git://git.kernel.dk/linux-block:
Revert "block: reduce kblockd_mod_delayed_work_on() CPU consumption"
Pull irq fixes from Borislav Petkov:
- Clear the PCI_MSIX_FLAGS_MASKALL bit too on the error path so that it
is restored to its reset state
- Mask MSI-X vectors late on the init path in order to handle
out-of-spec Marvell NVME devices which apparently look at the MSI-X
mask even when MSI-X is disabled
* tag 'irq_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
PCI/MSI: Clear PCI_MSIX_FLAGS_MASKALL on error
PCI/MSI: Mask MSI-X vectors only on success
Pull timer fix from Borislav Petkov:
- Make sure the CLOCK_REALTIME to CLOCK_MONOTONIC offset is never
positive
* tag 'timers_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping: Really make sure wall_to_monotonic isn't positive
Pull locking fix from Borislav Petkov:
- Fix the rtmutex condition checking when the optimistic spinning of a
waiter needs to be terminated
* tag 'locking_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rtmutex: Fix incorrect condition in rtmutex_spin_on_owner()
Pull signal handlign fix from Borislav Petkov:
- Prevent lock contention on the new sigaltstack lock on the
common-case path, when no changes have been made to the alternative
signal stack.
* tag 'core_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
signal: Skip the altstack update when not needed
Pull MIPS fix from Thomas Bogendoerfer:
- only enable pci_remap_iospace() for Ralink devices
* tag 'mips-fixes_5.16_3' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: Only define pci_remap_iospace() for Ralink
Pull powerpc fixes from Michael Ellerman:
"Fix a recently introduced oops at boot on 85xx in some configurations.
Fix crashes when loading some livepatch modules with
STRICT_MODULE_RWX.
Thanks to Joe Lawrence, Russell Currey, and Xiaoming Ni"
* tag 'powerpc-5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/module_64: Fix livepatching for RO modules
powerpc/85xx: Fix oops when CONFIG_FSL_PMC=n
Pull cifs fixes from Steve French:
"Two cifs/smb3 fixes, one fscache related, and one mount parsing
related for stable"
* tag '5.16-rc5-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: sanitize multiple delimiters in prepath
cifs: ignore resource_id while getting fscache super cookie
Play nice with a NULL shadow page when checking for an obsolete root in
the page fault handler by flagging the page fault as stale if there's no
shadow page associated with the root and KVM_REQ_MMU_RELOAD is pending.
Invalidating memslots, which is the only case where _all_ roots need to
be reloaded, requests all vCPUs to reload their MMUs while holding
mmu_lock for lock.
The "special" roots, e.g. pae_root when KVM uses PAE paging, are not
backed by a shadow page. Running with TDP disabled or with nested NPT
explodes spectaculary due to dereferencing a NULL shadow page pointer.
Skip the KVM_REQ_MMU_RELOAD check if there is a valid shadow page for the
root. Zapping shadow pages in response to guest activity, e.g. when the
guest frees a PGD, can trigger KVM_REQ_MMU_RELOAD even if the current
vCPU isn't using the affected root. I.e. KVM_REQ_MMU_RELOAD can be seen
with a completely valid root shadow page. This is a bit of a moot point
as KVM currently unloads all roots on KVM_REQ_MMU_RELOAD, but that will
be cleaned up in the future.
Fixes: a955cad84c ("KVM: x86/mmu: Retry page fault if root is invalidated by memslot update")
Cc: stable@vger.kernel.org
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211209060552.2956723-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Host initiated writes to MSR_IA32_PERF_CAPABILITIES should not depend
on guest visible CPUIDs and (incorrect) KVM logic implementing it is
about to change. Also, KVM_SET_CPUID{,2} after KVM_RUN is now forbidden
and causes test to fail.
Reported-by: kernel test robot <oliver.sang@intel.com>
Fixes: feb627e8d6 ("KVM: x86: Forbid KVM_SET_CPUID{,2} after KVM_RUN")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211216165213.338923-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The ability to write to MSR_IA32_PERF_CAPABILITIES from the host should
not depend on guest visible CPUID entries, even if just to allow
creating/restoring guest MSRs and CPUIDs in any sequence.
Fixes: 27461da310 ("KVM: x86/pmu: Support full width counting")
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211216165213.338923-3-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull tty/serial fixes from Greg KH:
"Here are two small tty/serial fixes for 5.16-rc6. They include:
- n_hdlc fix for syzbot reported problem that you were previously
copied on.
- 8250_fintek driver fix that resolved a console problem by removing
a previous change.
Both have been in linux-next with no reported issues"
* tag 'tty-5.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: 8250_fintek: Fix garbled text for console
tty: n_hdlc: make n_hdlc_tty_wakeup() asynchronous
Pull USB fixes from Greg KH:
"Here are a number of small USB driver fixes for reported problems.
They include:
- dwc2 driver fixes
- xhci driver fixes
- cdnsp driver fixes
- typec driver fix
- gadget u_ether driver fix
- new quirk additions
- usb gadget endpoint calculation fix
- usb serial new device ids
- revert of a xhci-dbg change that broke early debug booting
All changes, except for the revert, have been in linux-next with no
reported problems. The revert was from yesterday, and it was reported
by the developers affected that it resolved their problem"
* tag 'usb-5.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
Revert "usb: early: convert to readl_poll_timeout_atomic()"
usb: typec: tcpm: fix tcpm unregister port but leave a pending timer
usb: cdnsp: Fix lack of spin_lock_irqsave/spin_lock_restore
USB: NO_LPM quirk Lenovo USB-C to Ethernet Adapher(RTL8153-04)
usb: xhci: Extend support for runtime power management for AMD's Yellow carp.
usb: dwc2: fix STM ID/VBUS detection startup delay in dwc2_driver_probe
USB: gadget: bRequestType is a bitfield, not a enum
USB: serial: option: add Telit FN990 compositions
USB: serial: cp210x: fix CP2105 GPIO registration
usb: cdnsp: Fix incorrect status for control request
usb: cdnsp: Fix issue in cdnsp_log_ep trace event
usb: cdnsp: Fix incorrect calling of cdnsp_died function
usb: xhci-mtk: fix list_del warning when enable list debug
usb: gadget: u_ether: fix race in setting MAC address in setup phase
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix segfaults in 'perf inject' related to usage of unopened files
- The return value of hashmap__new() should be checked using IS_ERR()
* tag 'perf-tools-fixes-for-v5.16-2021-12-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf inject: Fix segfault due to perf_data__fd() without open
perf inject: Fix segfault due to close without open
perf expr: Fix missing check for return value of hashmap__new()
The fixed commit attempts to get the output file descriptor even if the
file was never opened e.g.
$ perf record uname
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.002 MB perf.data (7 samples) ]
$ perf inject -i perf.data --vm-time-correlation=dry-run
Segmentation fault (core dumped)
$ gdb --quiet perf
Reading symbols from perf...
(gdb) r inject -i perf.data --vm-time-correlation=dry-run
Starting program: /home/ahunter/bin/perf inject -i perf.data --vm-time-correlation=dry-run
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Program received signal SIGSEGV, Segmentation fault.
__GI___fileno (fp=0x0) at fileno.c:35
35 fileno.c: No such file or directory.
(gdb) bt
#0 __GI___fileno (fp=0x0) at fileno.c:35
#1 0x00005621e48dd987 in perf_data__fd (data=0x7fff4c68bd08) at util/data.h:72
#2 perf_data__fd (data=0x7fff4c68bd08) at util/data.h:69
#3 cmd_inject (argc=<optimized out>, argv=0x7fff4c69c1f0) at builtin-inject.c:1017
#4 0x00005621e4936783 in run_builtin (p=0x5621e4ee6878 <commands+600>, argc=4, argv=0x7fff4c69c1f0) at perf.c:313
#5 0x00005621e4897d5c in handle_internal_command (argv=<optimized out>, argc=<optimized out>) at perf.c:365
#6 run_argv (argcp=<optimized out>, argv=<optimized out>) at perf.c:409
#7 main (argc=4, argv=0x7fff4c69c1f0) at perf.c:539
(gdb)
Fixes: 0ae0389362 ("perf tools: Pass a fd to perf_file_header__read_pipe()")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/20211213084829.114772-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The fixed commit attempts to close inject.output even if it was never
opened e.g.
$ perf record uname
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.002 MB perf.data (7 samples) ]
$ perf inject -i perf.data --vm-time-correlation=dry-run
Segmentation fault (core dumped)
$ gdb --quiet perf
Reading symbols from perf...
(gdb) r inject -i perf.data --vm-time-correlation=dry-run
Starting program: /home/ahunter/bin/perf inject -i perf.data --vm-time-correlation=dry-run
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Program received signal SIGSEGV, Segmentation fault.
0x00007eff8afeef5b in _IO_new_fclose (fp=0x0) at iofclose.c:48
48 iofclose.c: No such file or directory.
(gdb) bt
#0 0x00007eff8afeef5b in _IO_new_fclose (fp=0x0) at iofclose.c:48
#1 0x0000557fc7b74f92 in perf_data__close (data=data@entry=0x7ffcdafa6578) at util/data.c:376
#2 0x0000557fc7a6b807 in cmd_inject (argc=<optimized out>, argv=<optimized out>) at builtin-inject.c:1085
#3 0x0000557fc7ac4783 in run_builtin (p=0x557fc8074878 <commands+600>, argc=4, argv=0x7ffcdafb6a60) at perf.c:313
#4 0x0000557fc7a25d5c in handle_internal_command (argv=<optimized out>, argc=<optimized out>) at perf.c:365
#5 run_argv (argcp=<optimized out>, argv=<optimized out>) at perf.c:409
#6 main (argc=4, argv=0x7ffcdafb6a60) at perf.c:539
(gdb)
Fixes: 02e6246f53 ("perf inject: Close inject.output on exit")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/20211213084829.114772-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull libata fix from Damien Le Moal:
"A single fix for this cycle:
- Check that ATA16 passthrough commands that do not transfer any data
have a DMA direction set to DMA_NONE (From George)"
* tag 'libata-5.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata:
libata: if T_LENGTH is zero, dma direction should be DMA_NONE
Pull zonefs fixes from Damien Le Moal:
"One fix and one trivial update for rc6:
- Add MODULE_ALIAS_FS to get automatic module loading on mount
(Naohiro)
- Update Damien's email address in the MAINTAINERS file (me)"
* tag 'zonefs-5.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs:
MAITAINERS: Change zonefs maintainer email address
zonefs: add MODULE_ALIAS_FS
mount.cifs can pass a device with multiple delimiters in it. This will
cause rename(2) to fail with ENOENT.
V2:
- Make sanitize_path more readable.
- Fix multiple delimiters between UNC and prepath.
- Avoid a memory leak if a bad user starts putting a lot of delimiters
in the path on purpose.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=2031200
Fixes: 24e0a1eff9 ("cifs: switch to new mount api")
Cc: stable@vger.kernel.org # 5.11+
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Thiago Rafael Becker <trbecker@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We have a cyclic dependency between fscache super cookie
and root inode cookie. The super cookie relies on
tcon->resource_id, which gets populated from the root inode
number. However, fetching the root inode initializes inode
cookie as a child of super cookie, which is yet to be populated.
resource_id is only used as auxdata to check the validity of
super cookie. We can completely avoid setting resource_id to
remove the circular dependency. Since vol creation time and
vol serial numbers are used for auxdata, we should be fine.
Additionally, there will be auxiliary data check for each
inode cookie as well.
Fixes: 5bf91ef03d ("cifs: wait for tcon resource_id before getting fscache super")
CC: David Howells <dhowells@redhat.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Even after commit e1d7ba8735 ("time: Always make sure wall_to_monotonic
isn't positive") it is still possible to make wall_to_monotonic positive
by running the following code:
int main(void)
{
struct timespec time;
clock_gettime(CLOCK_MONOTONIC, &time);
time.tv_nsec = 0;
clock_settime(CLOCK_REALTIME, &time);
return 0;
}
The reason is that the second parameter of timespec64_compare(), ts_delta,
may be unnormalized because the delta is calculated with an open coded
substraction which causes the comparison of tv_sec to yield the wrong
result:
wall_to_monotonic = { .tv_sec = -10, .tv_nsec = 900000000 }
ts_delta = { .tv_sec = -9, .tv_nsec = -900000000 }
That makes timespec64_compare() claim that wall_to_monotonic < ts_delta,
but actually the result should be wall_to_monotonic > ts_delta.
After normalization, the result of timespec64_compare() is correct because
the tv_sec comparison is not longer misleading:
wall_to_monotonic = { .tv_sec = -10, .tv_nsec = 900000000 }
ts_delta = { .tv_sec = -10, .tv_nsec = 100000000 }
Use timespec64_sub() to ensure that ts_delta is normalized, which fixes the
issue.
Fixes: e1d7ba8735 ("time: Always make sure wall_to_monotonic isn't positive")
Signed-off-by: Yu Liao <liaoyu15@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211213135727.1656662-1-liaoyu15@huawei.com
Pull SCSI fix from James Bottomley:
"One driver fix: the pm8001 has never actually worked on a system with
an IOMMU and this fixes that use case"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: pm8001: Fix phys_to_virt() usage on dma_addr_t
Pull btrfs fixes from David Sterba:
"A few more fixes, almost all error handling one-liners and for stable.
- regression fix in directory logging items
- regression fix of extent buffer status bits handling after an error
- fix memory leak in error handling path in tree-log
- fix freeing invalid anon device number when handling errors during
subvolume creation
- fix warning when freeing leaf after subvolume creation failure
- fix missing blkdev put in device scan error handling
- fix invalid delayed ref after subvolume creation failure"
* tag 'for-5.16-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix missing blkdev_put() call in btrfs_scan_one_device()
btrfs: fix warning when freeing leaf after subvolume creation failure
btrfs: fix invalid delayed ref after subvolume creation failure
btrfs: check WRITE_ERR when trying to read an extent buffer
btrfs: fix missing last dir item offset update when logging directory
btrfs: fix double free of anon_dev after failure to create subvolume
btrfs: fix memory leak in __add_inode_ref()
Pull selinux fix from Paul Moore:
"Another small SELinux fix for v5.16 to ensure that we don't block on
memory allocations while holding a spinlock.
This passes all our tests without problem"
* tag 'selinux-pr-20211217' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: fix sleeping function called from invalid context
Pull RISC-V fixes from Palmer Dabbelt:
- A handful of DT updates for the SiFive HiFive Unmatched, that fix the
regulator handling. These should stop some warning spew.
- A pair of fixes for both the SiFive Hifive Unleashed and Unmatched,
that correctly hook up the MMC card detect signal.
* tag 'riscv-for-linus-5.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: dts: sifive unmatched: Link the tmp451 with its power supply
riscv: dts: sifive unmatched: Fix regulator for board rev3
riscv: dts: sifive unmatched: Expose the PMIC sub-functions
riscv: dts: sifive unmatched: Expose the board ID eeprom
riscv: dts: sifive unmatched: Name gpio lines
riscv: dts: unmatched: Add gpio card detect to mmc-spi-slot
riscv: dts: unleashed: Add gpio card detect to mmc-spi-slot
Pull block fixes from Jens Axboe:
- Fix for hammering on the delayed run queue timer (me)
- bcache regression fix for this merge window (Lin)
- Fix a divide-by-zero in the blk-iocost code (Tejun)
* tag 'block-5.16-2021-12-17' of git://git.kernel.dk/linux-block:
bcache: fix NULL pointer reference in cached_dev_detach_finish
block: reduce kblockd_mod_delayed_work_on() CPU consumption
iocost: Fix divide-by-zero on donation from low hweight cgroup
Pull io_uring fix from Jens Axboe:
"Just a single fix, fixing an issue with the worker creation change
that was merged last week"
* tag 'io_uring-5.16-2021-12-17' of git://git.kernel.dk/linux-block:
io-wq: drop wqe lock before creating new worker
