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Linux kernel
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Remove a confusing comment on our local_flush_tlb_all()
implementation. Per an internal discussion with Andrew, while it's
true that the fence.i is not necessary, it's not the case that an
sfence.vma implies a fence.i. We also drop the section about
"flush[ing] the entire local TLB" to better align with the language in
section 4.2.1 "Supervisor Memory-Management Fence Instruction" of the
RISC-V Privileged Specification v20190608.
Fixes: c901e45a999a1 ("RISC-V: `sfence.vma` orderes the instruction cache")
Reported-by: Alan Kao <alankao@andestech.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Andrew Waterman <andrew@sifive.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Add a default "stdout-path" to the kernel DTS file, as is present in many
of the board DTS files elsewhere in the kernel tree. With this line
present, earlyconsole can be enabled by simply passing "earlycon" on the
kernel command line. No specific device details are necessary, since the
kernel will use the stdout-path as the default.
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
To make the code more straightforward, replace the switch statement
with an if statement.
Suggested-by: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
[paul.walmsley@sifive.com: cleaned up patch description; updated to
apply]
Link: https://lore.kernel.org/linux-riscv/20190927224711.GI4700@infradead.org/
Link: https://lore.kernel.org/linux-riscv/CABvJ_xiHJSB7P5QekuLRP=LBPzXXghAfuUpPUYb=a_HbnOQ6BA@mail.gmail.com/
Link: https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org/thread/VDCU2WOB6KQISREO4V5DTXEI2M7VOV55/
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
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")
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>
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>
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
Commit 7e534323c416 ("mtd: rawnand: Pass a nand_chip object to
chip->read_xxx() hooks") modified the prototype of the struct nand_chip
read_buf function pointer. In the au1550nd driver we have 2
implementations of read_buf. The previously mentioned commit modified
the au_read_buf() implementation to match the function pointer, but not
au_read_buf16(). This results in a compiler warning for MIPS
db1xxx_defconfig builds:
drivers/mtd/nand/raw/au1550nd.c:443:57:
warning: pointer type mismatch in conditional expression
Fix this by updating the prototype of au_read_buf16() to take a struct
nand_chip pointer as its first argument, as is expected after commit
7e534323c416 ("mtd: rawnand: Pass a nand_chip object to chip->read_xxx()
hooks").
Note that this shouldn't have caused any functional issues at runtime,
since the offset of the struct mtd_info within struct nand_chip is 0
making mtd_to_nand() effectively a type-cast.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 7e534323c416 ("mtd: rawnand: Pass a nand_chip object to chip->read_xxx() hooks")
Cc: stable@vger.kernel.org # v4.20+
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
SMI# interrupt for fan and voltage is Two-Times Interrupt Mode.
Fan or voltage exceeds high limit or going below low limit,
it will causes an interrupt if the previous interrupt has been
reset by reading all the interrupt Status Register. Thus, add the
array fan_alarm and vsen_alarm to store the alarms for all of the
fan and voltage sensors.
Signed-off-by: amy.shih <amy.shih@advantech.com.tw>
Link: https://lore.kernel.org/r/20190919030205.11440-1-Amy.Shih@advantech.com.tw
Fixes: 486842db3b79 ("hwmon: (nct7904) Add extra sysfs support for fan, voltage and temperature.")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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