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Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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Pull irqchip fixes from Marc Zyngier:
- Add retrigger support to Amazon's al-fic driver
- Add SAM9X60 support to Atmel's AIC5 irqchip
- Fix GICv3 maximum interrupt calculation
- Convert SiFive's PLIC to the fasteoi IRQ flow
The SiFive PLIC interrupt controller seems to have all the HW
features to support the fasteoi flow, but the driver seems to be
stuck in a distant past. Bring it into the 21st century.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Tested-by: Palmer Dabbelt <palmer@sifive.com> (QEMU Boot)
Tested-by: Darius Rad <darius@bluespec.com> (on 2 HW PLIC implementations)
Tested-by: Paul Walmsley <paul.walmsley@sifive.com> (HiFive Unleashed)
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/8636gxskmj.wl-maz@kernel.org
Pull tracing fixes from Steven Rostedt:
"A few tracing fixes:
- Remove lockdown from tracefs itself and moved it to the trace
directory. Have the open functions there do the lockdown checks.
- Fix a few races with opening an instance file and the instance
being deleted (Discovered during the lockdown updates). Kept
separate from the clean up code such that they can be backported to
stable easier.
- Clean up and consolidated the checks done when opening a trace
file, as there were multiple checks that need to be done, and it
did not make sense having them done in each open instance.
- Fix a regression in the record mcount code.
- Small hw_lat detector tracer fixes.
- A trace_pipe read fix due to not initializing trace_seq"
* tag 'trace-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Initialize iter->seq after zeroing in tracing_read_pipe()
tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency
tracing/hwlat: Report total time spent in all NMIs during the sample
recordmcount: Fix nop_mcount() function
tracing: Do not create tracefs files if tracefs lockdown is in effect
tracing: Add locked_down checks to the open calls of files created for tracefs
tracing: Add tracing_check_open_get_tr()
tracing: Have trace events system open call tracing_open_generic_tr()
tracing: Get trace_array reference for available_tracers files
ftrace: Get a reference counter for the trace_array on filter files
tracefs: Revert ccbd54ff54e8 ("tracefs: Restrict tracefs when the kernel is locked down")
As per GIC spec, ITLinesNumber indicates the maximum SPI INTID that
the GIC implementation supports. And the maximum SPI INTID an
implementation might support is 1019 (field value 11111).
max(GICD_TYPER_SPIS(...), 1020) is not what we actually want for
GIC_LINE_NR. Fix it to min(GICD_TYPER_SPIS(...), 1020).
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1568789850-14080-1-git-send-email-yuzenghui@huawei.com
Merge tag 'hwmon-for-v5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon fixes from Guenter Roeck:
- Update/fix inspur-ipsps1 and k10temp Documentation
- Fix nct7904 driver
- Fix HWMON_P_MIN_ALARM mask in hwmon core
* tag 'hwmon-for-v5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: docs: Extend inspur-ipsps1 title underline
hwmon: (nct7904) Add array fan_alarm and vsen_alarm to store the alarms in nct7904_data struct.
docs: hwmon: Include 'inspur-ipsps1.rst' into docs
hwmon: Fix HWMON_P_MIN_ALARM mask
hwmon: (k10temp) Update documentation and add temp2_input info
hwmon: (nct7904) Fix the incorrect value of vsen_mask in nct7904_data struct
A customer reported the following softlockup:
[899688.160002] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [test.sh:16464]
[899688.160002] CPU: 0 PID: 16464 Comm: test.sh Not tainted 4.12.14-6.23-azure #1 SLE12-SP4
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] Kernel panic - not syncing: softlockup: hung tasks
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] RSP: 0018:ffffa86784d4fde8 EFLAGS: 00000257 ORIG_RAX: ffffffffffffff12
[899688.160002] RAX: ffffffff970fea00 RBX: 0000000000000001 RCX: 0000000000000000
[899688.160002] RDX: ffffffff00000001 RSI: 0000000000000080 RDI: ffffffff970fea00
[899688.160002] RBP: ffffffffffffffff R08: ffffffffffffffff R09: 0000000000000000
[899688.160002] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8b59014720d8
[899688.160002] R13: ffff8b59014720c0 R14: ffff8b5901471090 R15: ffff8b5901470000
[899688.160002] tracing_read_pipe+0x336/0x3c0
[899688.160002] __vfs_read+0x26/0x140
[899688.160002] vfs_read+0x87/0x130
[899688.160002] SyS_read+0x42/0x90
[899688.160002] do_syscall_64+0x74/0x160
It caught the process in the middle of trace_access_unlock(). There is
no loop. So, it must be looping in the caller tracing_read_pipe()
via the "waitagain" label.
Crashdump analyze uncovered that iter->seq was completely zeroed
at this point, including iter->seq.seq.size. It means that
print_trace_line() was never able to print anything and
there was no forward progress.
The culprit seems to be in the code:
/* reset all but tr, trace, and overruns */
memset(&iter->seq, 0,
sizeof(struct trace_iterator) -
offsetof(struct trace_iterator, seq));
It was added by the commit 53d0aa773053ab182877 ("ftrace:
add logic to record overruns"). It was v2.6.27-rc1.
It was the time when iter->seq looked like:
struct trace_seq {
unsigned char buffer[PAGE_SIZE];
unsigned int len;
};
There was no "size" variable and zeroing was perfectly fine.
The solution is to reinitialize the structure after or without
zeroing.
Link: http://lkml.kernel.org/r/20191011142134.11997-1-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add support for SAM9X60 irqchip.
Signed-off-by: Sandeep Sheriker Mallikarjun <sandeepsheriker.mallikarjun@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1568026835-6646-1-git-send-email-claudiu.beznea@microchip.com
[claudiu.beznea@microchip.com: update aic5_irq_fixups[], update
documentation]
Pull MTD fixes from Richard Weinberger:
"Two fixes for MTD:
- spi-nor: Fix for a regression in write_sr()
- rawnand: Regression fix for the au1550nd driver"
* tag 'fixes-for-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux:
mtd: rawnand: au1550nd: Fix au_read_buf16() prototype
mtd: spi-nor: Fix direction of the write_sr() transfer
Sphinx is generating a build warning as the title underline
of this file is too short.
Signed-off-by: Adam Zerella <adam.zerella@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
max_latency is intended to record the maximum ever observed hardware
latency, which may occur in either part of the loop (inner/outer). So
we need to also consider the outer-loop sample when updating
max_latency.
Link: http://lkml.kernel.org/r/157073345463.17189.18124025522664682811.stgit@srivatsa-ubuntu
Fixes: e7c15cd8a113 ("tracing: Added hardware latency tracer")
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Introduce interrupts retrigger support for Amazon's Annapurna Labs Fabric
Interrupt Controller.
Signed-off-by: Talel Shenhar <talel@amazon.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1568018358-18985-1-git-send-email-talel@amazon.com
Pull io_uring fix from Jens Axboe:
"Single small fix for a regression in the sequence logic for linked
commands"
* tag 'for-linus-20191012' of git://git.kernel.dk/linux-block:
io_uring: fix sequence logic for timeout requests
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