This series fixes two bugs in the RTW88 USB driver I was reported from
several people and that I also encountered myself.
The first one resulted in "timed out to flush queue 3" messages from the
driver and sometimes a complete stall of the TX queues.
The second one is specific to the RTW8821CU chipset. Here 2GHz networks
were hardly seen and impossible to connect to. This goes down to
misinterpreting the rfe_option field in the efuse.
Sascha Hauer (2):
wifi: rtw88: usb: fix priority queue to endpoint mapping
wifi: rtw88: rtw8821c: Fix rfe_option field width
drivers/net/wireless/realtek/rtw88/rtw8821c.c | 3 +-
drivers/net/wireless/realtek/rtw88/usb.c | 70 +++++++++++++------
2 files changed, 48 insertions(+), 25 deletions(-)
--
2.39.2
From: Hui Li <caelli(a)tencent.com>
We have met a hang on pty device, the reader was blocking
at epoll on master side, the writer was sleeping at wait_woken
inside n_tty_write on slave side, and the write buffer on
tty_port was full, we found that the reader and writer would
never be woken again and blocked forever.
The problem was caused by a race between reader and kworker:
n_tty_read(reader): n_tty_receive_buf_common(kworker):
copy_from_read_buf()|
|room = N_TTY_BUF_SIZE - (ldata->read_head - tail)
|room <= 0
n_tty_kick_worker() |
|ldata->no_room = true
After writing to slave device, writer wakes up kworker to flush
data on tty_port to reader, and the kworker finds that reader
has no room to store data so room <= 0 is met. At this moment,
reader consumes all the data on reader buffer and calls
n_tty_kick_worker to check ldata->no_room which is false and
reader quits reading. Then kworker sets ldata->no_room=true
and quits too.
If write buffer is not full, writer will wake kworker to flush data
again after following writes, but if write buffer is full and writer
goes to sleep, kworker will never be woken again and tty device is
blocked.
This problem can be solved with a check for read buffer size inside
n_tty_receive_buf_common, if read buffer is empty and ldata->no_room
is true, a call to n_tty_kick_worker is necessary to keep flushing
data to reader.
Cc: <stable(a)vger.kernel.org>
Fixes: 42458f41d08f ("n_tty: Ensure reader restarts worker for next reader")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen(a)linux.intel.com>
Signed-off-by: Hui Li <caelli(a)tencent.com>
---
Patch changelogs between v1 and v2:
-add barrier inside n_tty_read and n_tty_receive_buf_common;
-comment why barrier is needed;
-access to ldata->no_room is changed with READ_ONCE and WRITE_ONCE;
Patch changelogs between v2 and v3:
-in function n_tty_receive_buf_common, add unlikely to check
ldata->no_room, eg: if (unlikely(ldata->no_room)), and READ_ONCE
is removed here to get locality;
-change comment for barrier to show the race condition to make
comment easier to understand;
Patch changelogs between v3 and v4:
-change subject from 'tty: fix a possible hang on tty device' to
'tty: fix hang on tty device with no_room set' to make subject
more obvious;
Patch changelogs between v4 and v5:
-name is changed from cael to caelli, li is added as the family
name and caelli is the fullname.
Patch changelogs between v5 and v6:
-change from and Signed-off-by, from 'caelli <juanfengpy(a)gmail.com>'
to 'caelli <caelli(a)tencent.com>', later one is my corporate address.
Patch changelogs between v6 and v7:
-change name from caelli to 'Hui Li', which is my name in chinese.
-the comment for barrier is improved, and a Fixes and Reviewed-by
tags is added.
drivers/tty/n_tty.c | 41 +++++++++++++++++++++++++++++++++++++----
1 file changed, 37 insertions(+), 4 deletions(-)
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index c8f56c9b1a1c..8c17304fffcf 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -204,8 +204,8 @@ static void n_tty_kick_worker(struct tty_struct *tty)
struct n_tty_data *ldata = tty->disc_data;
/* Did the input worker stop? Restart it */
- if (unlikely(ldata->no_room)) {
- ldata->no_room = 0;
+ if (unlikely(READ_ONCE(ldata->no_room))) {
+ WRITE_ONCE(ldata->no_room, 0);
WARN_RATELIMIT(tty->port->itty == NULL,
"scheduling with invalid itty\n");
@@ -1698,7 +1698,7 @@ n_tty_receive_buf_common(struct tty_struct *tty, const unsigned char *cp,
if (overflow && room < 0)
ldata->read_head--;
room = overflow;
- ldata->no_room = flow && !room;
+ WRITE_ONCE(ldata->no_room, flow && !room);
} else
overflow = 0;
@@ -1729,6 +1729,27 @@ n_tty_receive_buf_common(struct tty_struct *tty, const unsigned char *cp,
} else
n_tty_check_throttle(tty);
+ if (unlikely(ldata->no_room)) {
+ /*
+ * Barrier here is to ensure to read the latest read_tail in
+ * chars_in_buffer() and to make sure that read_tail is not loaded
+ * before ldata->no_room is set, otherwise, following race may occur:
+ * n_tty_receive_buf_common()
+ * n_tty_read()
+ * if (!chars_in_buffer(tty))->false
+ * copy_from_read_buf()
+ * read_tail=commit_head
+ * n_tty_kick_worker()
+ * if (ldata->no_room)->false
+ * ldata->no_room = 1
+ * Then both kworker and reader will fail to kick n_tty_kick_worker(),
+ * smp_mb is paired with smp_mb() in n_tty_read().
+ */
+ smp_mb();
+ if (!chars_in_buffer(tty))
+ n_tty_kick_worker(tty);
+ }
+
up_read(&tty->termios_rwsem);
return rcvd;
@@ -2282,8 +2303,25 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
if (time)
timeout = time;
}
- if (old_tail != ldata->read_tail)
+ if (old_tail != ldata->read_tail) {
+ /*
+ * Make sure no_room is not read in n_tty_kick_worker()
+ * before setting ldata->read_tail in copy_from_read_buf(),
+ * otherwise, following race may occur:
+ * n_tty_read()
+ * n_tty_receive_buf_common()
+ * n_tty_kick_worker()
+ * if(ldata->no_room)->false
+ * ldata->no_room = 1
+ * if (!chars_in_buffer(tty))->false
+ * copy_from_read_buf()
+ * read_tail=commit_head
+ * Both reader and kworker will fail to kick tty_buffer_restart_work(),
+ * smp_mb is paired with smp_mb() in n_tty_receive_buf_common().
+ */
+ smp_mb();
n_tty_kick_worker(tty);
+ }
up_read(&tty->termios_rwsem);
remove_wait_queue(&tty->read_wait, &wait);
--
2.27.0
Remove the EDO mode support from as the FMC2 controller does not
support the feature.
Signed-off-by: Christophe Kerello <christophe.kerello(a)foss.st.com>
Fixes: 2cd457f328c1 ("mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash controller driver")
Cc: stable(a)vger.kernel.org #v5.4+
Reviewed-by: Tudor Ambarus <tudor.ambarus(a)linaro.org>
---
Changes in v3:
- The commit message has been reworked
- Cc to stable added
- Tudor Reviewed-by added
drivers/mtd/nand/raw/stm32_fmc2_nand.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/mtd/nand/raw/stm32_fmc2_nand.c b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
index 5d627048c420..3abb63d00a0b 100644
--- a/drivers/mtd/nand/raw/stm32_fmc2_nand.c
+++ b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
@@ -1531,6 +1531,9 @@ static int stm32_fmc2_nfc_setup_interface(struct nand_chip *chip, int chipnr,
if (IS_ERR(sdrt))
return PTR_ERR(sdrt);
+ if (sdrt->tRC_min < 30000)
+ return -EOPNOTSUPP;
+
if (chipnr == NAND_DATA_IFACE_CHECK_ONLY)
return 0;
--
2.25.1
When upreving llvm I realised that kexec stopped working on my test
platform. This patch fixes it.
Signed-off-by: Ricardo Ribalda <ribalda(a)chromium.org>
---
Changes in v5:
- Add warning when multiple text sections are found. Thanks Simon!
- Add Fixes tag.
- Link to v4: https://lore.kernel.org/r/20230321-kexec_clang16-v4-0-1340518f98e9@chromium…
Changes in v4:
- Add Cc: stable
- Add linker script for x86
- Add a warning when the kernel image has overlapping sections.
- Link to v3: https://lore.kernel.org/r/20230321-kexec_clang16-v3-0-5f016c8d0e87@chromium…
Changes in v3:
- Fix initial value. Thanks Ross!
- Link to v2: https://lore.kernel.org/r/20230321-kexec_clang16-v2-0-d10e5d517869@chromium…
Changes in v2:
- Fix if condition. Thanks Steven!.
- Update Philipp email. Thanks Baoquan.
- Link to v1: https://lore.kernel.org/r/20230321-kexec_clang16-v1-0-a768fc2c7c4d@chromium…
---
Ricardo Ribalda (2):
kexec: Support purgatories with .text.hot sections
x86/purgatory: Add linker script
arch/x86/purgatory/.gitignore | 2 ++
arch/x86/purgatory/Makefile | 20 +++++++++----
arch/x86/purgatory/kexec-purgatory.S | 2 +-
arch/x86/purgatory/purgatory.lds.S | 57 ++++++++++++++++++++++++++++++++++++
kernel/kexec_file.c | 14 ++++++++-
5 files changed, 87 insertions(+), 8 deletions(-)
---
base-commit: 17214b70a159c6547df9ae204a6275d983146f6b
change-id: 20230321-kexec_clang16-4510c23d129c
Best regards,
--
Ricardo Ribalda <ribalda(a)chromium.org>
Hi,
I am running kernel 6.1 on a system with a mv88e6320 and can easily
trigger a flood of "mv88e6085 30be0000.ethernet-1:00: VTU member
violation for vid 10, source port 5" messages.
When this happens, the Ethernet audio that passes through the switch
causes a loud noise in the speaker.
Backporting the following commits to 6.1 solves the problem:
4bf24ad09bc0 ("net: dsa: mv88e6xxx: read FID when handling ATU violations")
8646384d80f3 ("net: dsa: mv88e6xxx: replace ATU violation prints with
trace points")
9e3d9ae52b56 ("net: dsa: mv88e6xxx: replace VTU violation prints with
trace points")
Please apply them to 6.1-stable tree.
Thanks,
Fabio Estevam
I am very sorry. My gcc version is 7.5 and it does not report error.
We have a deadlock problem which can be solved by commit 4f7e7236435ca
("cgroup: Fix threadgroup_rwsem <-> cpus_read_lock() deadlock").
However, it makes lock order of cpus_read_lock and cpuset_mutex
wrong in v4.19. The call sequence is as follows:
cgroup_procs_write()
cgroup_procs_write_start()
get_online_cpus(); // cpus_read_lock()
percpu_down_write(&cgroup_threadgroup_rwsem)
cgroup_attach_task
cgroup_migrate
cgroup_migrate_execute
ss->attach (cpust_attach)
mutex_lock(&cpuset_mutex)
it seems hard to make cpus_read_lock is locked before
cgroup_threadgroup_rwsem and cpuset_mutex is locked before
cpus_read_lock unless backport the commit d74b27d63a8beb
("cgroup/cpuset: Change cpuset_rwsem and hotplug lock order")
Changes in v2:
* Add #include <linux/cpu.h> in kernel/cgroup/cgroup.c to
avoid some compile error.
* Exchange get_online_cpus() location in cpuset_attach to
keep cpu_hotplug_lock->cpuset_mutex order, although it will
be remove by ("cgroup: Fix threadgroup_rwsem <->
cpus_read_lock() deadlock")
Juri Lelli (1):
cgroup/cpuset: Change cpuset_rwsem and hotplug lock order
Tejun Heo (1):
cgroup: Fix threadgroup_rwsem <-> cpus_read_lock() deadlock
Tetsuo Handa (1):
cgroup: Add missing cpus_read_lock() to cgroup_attach_task_all()
include/linux/cpuset.h | 8 +++----
kernel/cgroup/cgroup-v1.c | 3 +++
kernel/cgroup/cgroup.c | 50 +++++++++++++++++++++++++++++++++++----
kernel/cgroup/cpuset.c | 25 ++++++++++++--------
4 files changed, 67 insertions(+), 19 deletions(-)
--
2.17.1