SBSA says of the generic watchdog:
All registers are 32 bits in size and should be accessed using 32-bit
reads and writes. If an access size other than 32 bits is used then
the results are IMPLEMENTATION DEFINED.
and for qemu, the implementation will only allow 32-bit accesses
resulting in a synchronous external abort when configuring the watchdog.
Use lo_hi_* accessors rather than a readq/writeq.
Fixes: abd3ac7902 ("watchdog: sbsa: Support architecture version 1")
Signed-off-by: Jamie Iles <quic_jiles@quicinc.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Link: https://lore.kernel.org/r/20210903112101.493552-1-quic_jiles@quicinc.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
This reverts commit cb011044e3 ("watchdog: iTCO_wdt: Account for
rebooting on second timeout") and commit aec42642d9 ("watchdog: iTCO_wdt:
Fix detection of SMI-off case") since those patches cause a regression
on certain boards (https://bugzilla.kernel.org/show_bug.cgi?id=213809).
While this revert may result in some boards to only reset after twice
the configured timeout value, that is still better than a watchdog reset
after half the configured value.
Fixes: cb011044e3 ("watchdog: iTCO_wdt: Account for rebooting on second timeout")
Fixes: aec42642d9 ("watchdog: iTCO_wdt: Fix detection of SMI-off case")
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Mantas Mikulėnas <grawity@gmail.com>
Reported-by: Javier S. Pedro <debbugs@javispedro.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20211008003302.1461733-1-linux@roeck-us.net
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
ARM_QCOM_SPM_CPUIDLE can be selected when compile-testing on
other architectures, but this causes a Kconfig warning
for QCOM_SPM:
WARNING: unmet direct dependencies detected for QCOM_SPM
Depends on [n]: ARCH_QCOM [=n]
Selected by [y]:
- ARM_QCOM_SPM_CPUIDLE [=y] && CPU_IDLE [=y] && (ARM [=y] || ARM64) && (ARCH_QCOM [=n] || COMPILE_TEST [=y]) && !ARM64 && MMU [=y]
Make it possible to also compile-test this one, which can
be done now that v5.15-rc5 lets you select QCOM_SCM everywhere.
Fixes: a871be6b8e ("cpuidle: Convert Qualcomm SPM driver to a generic CPUidle driver")
Fixes: 498ba2a8a2 ("cpuidle: Fix ARM_QCOM_SPM_CPUIDLE configuration")
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Alderlake-P was getting 'max time under evasion' messages when PSR2
is enabled, this is due PIPE_SCANLINE/PIPEDSL returning 0 over a
period of time longer than VBLANK_EVASION_TIME_US.
For PSR1 we had the same issue so intel_psr_wait_for_idle() was
implemented to wait for PSR1 to get into idle state but nothing was
done for PSR2.
For PSR2 we can't only wait for idle state as PSR2 tends to keep
into sleep state(ready to send selective updates).
Waiting for any state below deep sleep proved to be effective in
avoiding the evasion messages and also not wasted a lot of time.
v2:
- dropping the additional wait_for loops, only the _wait_for_atomic()
is necessary
- waiting for states below EDP_PSR2_STATUS_STATE_DEEP_SLEEP
v3:
- dropping intel_wait_for_condition_atomic() function
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211005231851.67698-1-jose.souza@intel.com
Driver uses already twice the same string literal.
Define it in one place, so every user will have this
name consistent.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211025135148.53944-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Instead of putting garbage in the data structure, assign allocated id
or an error code to a temporary variable. This makes code cleaner.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211025135148.53944-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Data may be stored in DMA RX buffer, when suspending. The data needs
to be pushed to the upper layer. We can't rely on the timeout IRQ (RTOR)
that can't be triggered into low power state. So safely clear DMA request
(DMAR), force the DMA reception routines to push RX buffer content, before
disabling RX DMA. This way, handover to pio mode is safe.
Only call tty_flip_buffer_push() when there is RX data to handle.
Move the locking outside of stm32_usart_receive_chars() to prevent a race
condition, when disabling DMA request upon suspend / pm_runtime_suspend.
Data may be received under IRQ and pushed before
stm32_usart_receive_chars() has pushed older data from DMA rx_buf upon
suspend.
The sequence in suspend routine needs proper locking to avoid this.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-4-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
DMA prevents the system to suspend when an UART RX wake-up source is
using DMA. DMA can't suspend while DMA channels are still active.
Terminate DMA transfer at suspend, and restart a new DMA transfer at
resume. Create stm32_usart_start_rx_dma_cyclic function to factorize
dma RX initialization. Move RX DMA code related to wakeup into
stm32_usart_serial_en_wakeup() routine to ease further improvements
on wakeup from low power modes.
Don't enable/disable wakeup on uninitialized port.
There may be data residue in the RX FIFO while suspending. Flush it at
suspend time. Receiver timeout interrupt won't trigger later in low power
mode, so call stm32_usart_receive_chars() in case there's data to handle.
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-3-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The RX DMA channel is kept active forever (from the probe). That prevents
going to low power mode when it is used. This change moves the
DMA configuration and enabling procedures to startup routine to allow
transition to low power mode.
The DMA disabling procedure is implemented in stop_rx routine as this
ops has to stop characters reception, and DMA transation in shutdown.
Clean useless dma_async_tx_descriptor initialization to NULL value.
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-2-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
revert commit 46ae40b94d ("net/mlx5: Let user configure io_eq_size param")
revert commit a6cb08daa3 ("net/mlx5: Let user configure event_eq_size param")
revert commit 5546040619 ("net/mlx5: Let user configure max_macs param")
The EQE parameters are applicable to more drivers, they should
be configured via standard API, probably ethtool. Example of
another driver needing something similar:
https://lore.kernel.org/all/1633454136-14679-3-git-send-email-sbhatta@marvell.com/
The last param for "max_macs" is probably fine but the documentation
is severely lacking. The meaning and implications for changing the
param need to be stated.
Link: https://lore.kernel.org/r/20211026152939.3125950-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
xilinx_uartps .start_tx() clears TXEMPTY when enabling TXEMPTY to avoid
any previous TXEVENT event asserting the UART interrupt. This clear
operation is done immediately after filling the TX FIFO.
However, if the bytes inserted by cdns_uart_handle_tx() are consumed by
the UART before the TXEMPTY is cleared, the clear operation eats the new
TXEMPTY event as well, causing cdns_uart_isr() to never receive the
TXEMPTY event. If there are bytes still queued in circbuf, TX will get
stuck as they will never get transferred to FIFO (unless new bytes are
queued to circbuf in which case .start_tx() is called again).
While the racy missed TXEMPTY occurs fairly often with short data
sequences (e.g. write 1 byte), in those cases circbuf is usually empty
so no action on TXEMPTY would have been needed anyway. On the other
hand, longer data sequences make the race much more unlikely as UART
takes longer to consume the TX FIFO. Therefore it is rare for this race
to cause visible issues in general.
Fix the race by clearing the TXEMPTY bit in ISR *before* filling the
FIFO.
The TXEMPTY bit in ISR will only get asserted at the exact moment the
TX FIFO *becomes* empty, so clearing the bit before filling FIFO does
not cause an extra immediate assertion even if the FIFO is initially
empty.
This is hard to reproduce directly on a normal system, but inserting
e.g. udelay(200) after cdns_uart_handle_tx(port), setting 4000000 baud,
and then running "dd if=/dev/zero bs=128 of=/dev/ttyPS0 count=50"
reliably reproduces the issue on my ZynqMP test system unless this fix
is applied.
Fixes: 85baf542d5 ("tty: xuartps: support 64 byte FIFO size")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Link: https://lore.kernel.org/r/20211026102741.2910441-1-anssi.hannula@bitwise.fi
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If CONSOLE_POLL=n, CONFIG_SERIAL_SUNZILOG_CONSOLE=n, and CONFIG_SERIO=m:
drivers/tty/serial/sunzilog.c:1128:13: error: ‘sunzilog_putchar’ defined but not used [-Werror=unused-function]
1128 | static void sunzilog_putchar(struct uart_port *port, int ch)
| ^~~~~~~~~~~~~~~~
Fix this by marking sunzilog_putchar() __maybe_unused.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20211026080426.2444756-1-geert@linux-m68k.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In cases when functions are called via fwnode operations,
we already know that this is software node we are dealing
with, hence no need to check if it's NULL, it can't be,
Reported-by: YE Chengfeng <cyeaa@connect.ust.hk>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211026162954.89811-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB control-message timeouts are specified in milliseconds and should
specifically not vary with CONFIG_HZ.
Use the common control-message timeout define for the five-second
timeout and drop the driver-specific one.
Fixes: 946b960d13 ("USB: add driver for iowarrior devices.")
Cc: stable@vger.kernel.org # 2.6.21
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211025115159.4954-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB bulk-message timeouts are specified in milliseconds and should
specifically not vary with CONFIG_HZ.
Use a fixed five-second timeout in the "Writing USB Device Drivers"
example.
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211025115159.4954-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB control-message timeouts are specified in milliseconds and should
specifically not vary with CONFIG_HZ.
Use the common control-message timeout defines for the five-second
timeouts.
Fixes: 97a6f772f3 ("drivers: most: add USB adapter driver")
Cc: stable@vger.kernel.org # 5.9
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211025115811.5410-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB bulk and interrupt message timeouts are specified in milliseconds
and should specifically not vary with CONFIG_HZ.
Note that the bulk-out transfer timeout was set to the endpoint
bInterval value, which should be ignored for bulk endpoints and is
typically set to zero. This meant that a failing bulk-out transfer
would never time out.
Assume that the 10 second timeout used for all other transfers is more
than enough also for the bulk-out endpoint.
Fixes: 985cafccbf ("Staging: Comedi: vmk80xx: Add k8061 support")
Fixes: 951348b377 ("staging: comedi: vmk80xx: wait for URBs to complete")
Cc: stable@vger.kernel.org # 2.6.31
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20211025114532.4599-6-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver is using endpoint-sized buffers but must not assume that the
tx and rx buffers are of equal size or a malicious device could overflow
the slab-allocated receive buffer when doing bulk transfers.
Fixes: 985cafccbf ("Staging: Comedi: vmk80xx: Add k8061 support")
Cc: stable@vger.kernel.org # 2.6.31
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20211025114532.4599-5-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver uses endpoint-sized USB transfer buffers but up until
recently had no sanity checks on the sizes.
Commit e1f13c879a ("staging: comedi: check validity of wMaxPacketSize
of usb endpoints found") inadvertently fixed NULL-pointer dereferences
when accessing the transfer buffers in case a malicious device has a
zero wMaxPacketSize.
Make sure to allocate buffers large enough to handle also the other
accesses that are done without a size check (e.g. byte 18 in
vmk80xx_cnt_insn_read() for the VMK8061_MODEL) to avoid writing beyond
the buffers, for example, when doing descriptor fuzzing.
The original driver was for a low-speed device with 8-byte buffers.
Support was later added for a device that uses bulk transfers and is
presumably a full-speed device with a maximum 64-byte wMaxPacketSize.
Fixes: 985cafccbf ("Staging: Comedi: vmk80xx: Add k8061 support")
Cc: stable@vger.kernel.org # 2.6.31
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20211025114532.4599-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 95ea0486b2 ("btrfs: allow read-write for 4K sectorsize on 64K
page size systems") added write support for 4K sectorsize on a 64K
systems. Fix the now stale comments.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph pointed out that I'm updating bdev->bd_inode for the device
time when we remove block devices from a btrfs file system, however this
isn't actually exposed to anything. The inode we want to update is the
one that's associated with the path to the device, usually on devtmpfs,
so that blkid notices the difference.
We still don't want to do the blkdev_open, so use kern_path() to get the
path to the given device and do the update time on that inode.
Fixes: 8f96a5bfa1 ("btrfs: update the bdev time directly when closing")
Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If you already have an inode and need to update the time on the inode
there is no way to do this properly. Export this helper to allow file
systems to update time on the inode so the appropriate handler is
called, either ->update_time or generic_update_time.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Attempting to defragment a Btrfs file containing a transparent huge page
immediately deadlocks with the following stack trace:
#0 context_switch (kernel/sched/core.c:4940:2)
#1 __schedule (kernel/sched/core.c:6287:8)
#2 schedule (kernel/sched/core.c:6366:3)
#3 io_schedule (kernel/sched/core.c:8389:2)
#4 wait_on_page_bit_common (mm/filemap.c:1356:4)
#5 __lock_page (mm/filemap.c:1648:2)
#6 lock_page (./include/linux/pagemap.h:625:3)
#7 pagecache_get_page (mm/filemap.c:1910:4)
#8 find_or_create_page (./include/linux/pagemap.h:420:9)
#9 defrag_prepare_one_page (fs/btrfs/ioctl.c:1068:9)
#10 defrag_one_range (fs/btrfs/ioctl.c:1326:14)
#11 defrag_one_cluster (fs/btrfs/ioctl.c:1421:9)
#12 btrfs_defrag_file (fs/btrfs/ioctl.c:1523:9)
#13 btrfs_ioctl_defrag (fs/btrfs/ioctl.c:3117:9)
#14 btrfs_ioctl (fs/btrfs/ioctl.c:4872:10)
#15 vfs_ioctl (fs/ioctl.c:51:10)
#16 __do_sys_ioctl (fs/ioctl.c:874:11)
#17 __se_sys_ioctl (fs/ioctl.c:860:1)
#18 __x64_sys_ioctl (fs/ioctl.c:860:1)
#19 do_syscall_x64 (arch/x86/entry/common.c:50:14)
#20 do_syscall_64 (arch/x86/entry/common.c:80:7)
#21 entry_SYSCALL_64+0x7c/0x15b (arch/x86/entry/entry_64.S:113)
A huge page is represented by a compound page, which consists of a
struct page for each PAGE_SIZE page within the huge page. The first
struct page is the "head page", and the remaining are "tail pages".
Defragmentation attempts to lock each page in the range. However,
lock_page() on a tail page actually locks the corresponding head page.
So, if defragmentation tries to lock more than one struct page in a
compound page, it tries to lock the same head page twice and deadlocks
with itself.
Ideally, we should be able to defragment transparent huge pages.
However, THP for filesystems is currently read-only, so a lot of code is
not ready to use huge pages for I/O. For now, let's just return
ETXTBUSY.
This can be reproduced with the following on a kernel with
CONFIG_READ_ONLY_THP_FOR_FS=y:
$ cat create_thp_file.c
#include <fcntl.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/mman.h>
static const char zeroes[1024 * 1024];
static const size_t FILE_SIZE = 2 * 1024 * 1024;
int main(int argc, char **argv)
{
if (argc != 2) {
fprintf(stderr, "usage: %s PATH\n", argv[0]);
return EXIT_FAILURE;
}
int fd = creat(argv[1], 0777);
if (fd == -1) {
perror("creat");
return EXIT_FAILURE;
}
size_t written = 0;
while (written < FILE_SIZE) {
ssize_t ret = write(fd, zeroes,
sizeof(zeroes) < FILE_SIZE - written ?
sizeof(zeroes) : FILE_SIZE - written);
if (ret < 0) {
perror("write");
return EXIT_FAILURE;
}
written += ret;
}
close(fd);
fd = open(argv[1], O_RDONLY);
if (fd == -1) {
perror("open");
return EXIT_FAILURE;
}
/*
* Reserve some address space so that we can align the file mapping to
* the huge page size.
*/
void *placeholder_map = mmap(NULL, FILE_SIZE * 2, PROT_NONE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (placeholder_map == MAP_FAILED) {
perror("mmap (placeholder)");
return EXIT_FAILURE;
}
void *aligned_address =
(void *)(((uintptr_t)placeholder_map + FILE_SIZE - 1) & ~(FILE_SIZE - 1));
void *map = mmap(aligned_address, FILE_SIZE, PROT_READ | PROT_EXEC,
MAP_SHARED | MAP_FIXED, fd, 0);
if (map == MAP_FAILED) {
perror("mmap");
return EXIT_FAILURE;
}
if (madvise(map, FILE_SIZE, MADV_HUGEPAGE) < 0) {
perror("madvise");
return EXIT_FAILURE;
}
char *line = NULL;
size_t line_capacity = 0;
FILE *smaps_file = fopen("/proc/self/smaps", "r");
if (!smaps_file) {
perror("fopen");
return EXIT_FAILURE;
}
for (;;) {
for (size_t off = 0; off < FILE_SIZE; off += 4096)
((volatile char *)map)[off];
ssize_t ret;
bool this_mapping = false;
while ((ret = getline(&line, &line_capacity, smaps_file)) > 0) {
unsigned long start, end, huge;
if (sscanf(line, "%lx-%lx", &start, &end) == 2) {
this_mapping = (start <= (uintptr_t)map &&
(uintptr_t)map < end);
} else if (this_mapping &&
sscanf(line, "FilePmdMapped: %ld", &huge) == 1 &&
huge > 0) {
return EXIT_SUCCESS;
}
}
sleep(6);
rewind(smaps_file);
fflush(smaps_file);
}
}
$ ./create_thp_file huge
$ btrfs fi defrag -czstd ./huge
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 2efc459d06 ("sysfs: Add sysfs_emit and sysfs_emit_at to format
sysfs out") merged in 5.10 introduced two new functions sysfs_emit() and
sysfs_emit_at() which are aware of the PAGE_SIZE limit of the output
buffer.
Use the above two new functions instead of scnprintf() and snprintf()
in various sysfs show().
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's a common practice to avoid use sizeof(struct btrfs_super_block)
(3531), but to use BTRFS_SUPER_INFO_SIZE (4096).
The problem is that, sizeof(struct btrfs_super_block) doesn't match
BTRFS_SUPER_INFO_SIZE from the very beginning.
Furthermore, for all call sites except selftests, we always allocate
BTRFS_SUPER_INFO_SIZE space for super block, there isn't any real reason
to use the smaller value, and it doesn't really save any space.
So let's get rid of such confusing behavior, and unify those two values.
This modification also adds a new static_assert() to verify the size,
and moves the BTRFS_SUPER_INFO_* macros to the definition of
btrfs_super_block for the static_assert().
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Update the comments at btrfs_chunk_alloc() and do_chunk_alloc() that
describe which cases can lead to a failure to allocate metadata and system
space despite having previously reserved space. This adds one more reason
that I previously forgot to mention.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When a task is doing some modification to the chunk btree and it is not in
the context of a chunk allocation or a chunk removal, it can deadlock with
another task that is currently allocating a new data or metadata chunk.
These contexts are the following:
* When relocating a system chunk, when we need to COW the extent buffers
that belong to the chunk btree;
* When adding a new device (ioctl), where we need to add a new device item
to the chunk btree;
* When removing a device (ioctl), where we need to remove a device item
from the chunk btree;
* When resizing a device (ioctl), where we need to update a device item in
the chunk btree and may need to relocate a system chunk that lies beyond
the new device size when shrinking a device.
The problem happens due to a sequence of steps like the following:
1) Task A starts a data or metadata chunk allocation and it locks the
chunk mutex;
2) Task B is relocating a system chunk, and when it needs to COW an extent
buffer of the chunk btree, it has locked both that extent buffer as
well as its parent extent buffer;
3) Since there is not enough available system space, either because none
of the existing system block groups have enough free space or because
the only one with enough free space is in RO mode due to the relocation,
task B triggers a new system chunk allocation. It blocks when trying to
acquire the chunk mutex, currently held by task A;
4) Task A enters btrfs_chunk_alloc_add_chunk_item(), in order to insert
the new chunk item into the chunk btree and update the existing device
items there. But in order to do that, it has to lock the extent buffer
that task B locked at step 2, or its parent extent buffer, but task B
is waiting on the chunk mutex, which is currently locked by task A,
therefore resulting in a deadlock.
One example report when the deadlock happens with system chunk relocation:
INFO: task kworker/u9:5:546 blocked for more than 143 seconds.
Not tainted 5.15.0-rc3+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u9:5 state:D stack:25936 pid: 546 ppid: 2 flags:0x00004000
Workqueue: events_unbound btrfs_async_reclaim_metadata_space
Call Trace:
context_switch kernel/sched/core.c:4940 [inline]
__schedule+0xcd9/0x2530 kernel/sched/core.c:6287
schedule+0xd3/0x270 kernel/sched/core.c:6366
rwsem_down_read_slowpath+0x4ee/0x9d0 kernel/locking/rwsem.c:993
__down_read_common kernel/locking/rwsem.c:1214 [inline]
__down_read kernel/locking/rwsem.c:1223 [inline]
down_read_nested+0xe6/0x440 kernel/locking/rwsem.c:1590
__btrfs_tree_read_lock+0x31/0x350 fs/btrfs/locking.c:47
btrfs_tree_read_lock fs/btrfs/locking.c:54 [inline]
btrfs_read_lock_root_node+0x8a/0x320 fs/btrfs/locking.c:191
btrfs_search_slot_get_root fs/btrfs/ctree.c:1623 [inline]
btrfs_search_slot+0x13b4/0x2140 fs/btrfs/ctree.c:1728
btrfs_update_device+0x11f/0x500 fs/btrfs/volumes.c:2794
btrfs_chunk_alloc_add_chunk_item+0x34d/0xea0 fs/btrfs/volumes.c:5504
do_chunk_alloc fs/btrfs/block-group.c:3408 [inline]
btrfs_chunk_alloc+0x84d/0xf50 fs/btrfs/block-group.c:3653
flush_space+0x54e/0xd80 fs/btrfs/space-info.c:670
btrfs_async_reclaim_metadata_space+0x396/0xa90 fs/btrfs/space-info.c:953
process_one_work+0x9df/0x16d0 kernel/workqueue.c:2297
worker_thread+0x90/0xed0 kernel/workqueue.c:2444
kthread+0x3e5/0x4d0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
INFO: task syz-executor:9107 blocked for more than 143 seconds.
Not tainted 5.15.0-rc3+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:23200 pid: 9107 ppid: 7792 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:4940 [inline]
__schedule+0xcd9/0x2530 kernel/sched/core.c:6287
schedule+0xd3/0x270 kernel/sched/core.c:6366
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425
__mutex_lock_common kernel/locking/mutex.c:669 [inline]
__mutex_lock+0xc96/0x1680 kernel/locking/mutex.c:729
btrfs_chunk_alloc+0x31a/0xf50 fs/btrfs/block-group.c:3631
find_free_extent_update_loop fs/btrfs/extent-tree.c:3986 [inline]
find_free_extent+0x25cb/0x3a30 fs/btrfs/extent-tree.c:4335
btrfs_reserve_extent+0x1f1/0x500 fs/btrfs/extent-tree.c:4415
btrfs_alloc_tree_block+0x203/0x1120 fs/btrfs/extent-tree.c:4813
__btrfs_cow_block+0x412/0x1620 fs/btrfs/ctree.c:415
btrfs_cow_block+0x2f6/0x8c0 fs/btrfs/ctree.c:570
btrfs_search_slot+0x1094/0x2140 fs/btrfs/ctree.c:1768
relocate_tree_block fs/btrfs/relocation.c:2694 [inline]
relocate_tree_blocks+0xf73/0x1770 fs/btrfs/relocation.c:2757
relocate_block_group+0x47e/0xc70 fs/btrfs/relocation.c:3673
btrfs_relocate_block_group+0x48a/0xc60 fs/btrfs/relocation.c:4070
btrfs_relocate_chunk+0x96/0x280 fs/btrfs/volumes.c:3181
__btrfs_balance fs/btrfs/volumes.c:3911 [inline]
btrfs_balance+0x1f03/0x3cd0 fs/btrfs/volumes.c:4301
btrfs_ioctl_balance+0x61e/0x800 fs/btrfs/ioctl.c:4137
btrfs_ioctl+0x39ea/0x7b70 fs/btrfs/ioctl.c:4949
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
So fix this by making sure that whenever we try to modify the chunk btree
and we are neither in a chunk allocation context nor in a chunk remove
context, we reserve system space before modifying the chunk btree.
Reported-by: Hao Sun <sunhao.th@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/CACkBjsax51i4mu6C0C3vJqQN3NR_iVuucoeG3U1HXjrgzn5FFQ@mail.gmail.com/
Fixes: 79bd37120b ("btrfs: rework chunk allocation to avoid exhaustion of the system chunk array")
CC: stable@vger.kernel.org # 5.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently auto reclaim of unusable zones reclaims the block-groups in
the order they have been added to the reclaim list.
Change this to a greedy algorithm by sorting the list so we have the
block-groups with the least amount of valid bytes reclaimed first.
Note: we can't splice the block groups from reclaim_bgs to let the sort
happen outside of the lock. The block groups can be still in use by
other parts eg. via bg_list and we must hold unused_bgs_lock while
processing them.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ write note and comment why we can't splice the list ]
Signed-off-by: David Sterba <dsterba@suse.com>
Just use the %pg format specifier in all the debug printks previously
using it. Note that both bdevname and the %pg specifier never print
a pathname, so the kbasename call wasn't needed to start with.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
[ adjust messages and indentation ]
Signed-off-by: David Sterba <dsterba@suse.com>
For device removal and replace we call btrfs_find_device_by_devspec,
which if we give it a device path and nothing else will call
btrfs_get_dev_args_from_path, which opens the block device and reads the
super block and then looks up our device based on that.
However at this point we're holding the sb write "lock", so reading the
block device pulls in the dependency of ->open_mutex, which produces the
following lockdep splat
======================================================
WARNING: possible circular locking dependency detected
5.14.0-rc2+ #405 Not tainted
------------------------------------------------------
losetup/11576 is trying to acquire lock:
ffff9bbe8cded938 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0x67/0x5e0
but task is already holding lock:
ffff9bbe88e4fc68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (&lo->lo_mutex){+.+.}-{3:3}:
__mutex_lock+0x7d/0x750
lo_open+0x28/0x60 [loop]
blkdev_get_whole+0x25/0xf0
blkdev_get_by_dev.part.0+0x168/0x3c0
blkdev_open+0xd2/0xe0
do_dentry_open+0x161/0x390
path_openat+0x3cc/0xa20
do_filp_open+0x96/0x120
do_sys_openat2+0x7b/0x130
__x64_sys_openat+0x46/0x70
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
-> #3 (&disk->open_mutex){+.+.}-{3:3}:
__mutex_lock+0x7d/0x750
blkdev_get_by_dev.part.0+0x56/0x3c0
blkdev_get_by_path+0x98/0xa0
btrfs_get_bdev_and_sb+0x1b/0xb0
btrfs_find_device_by_devspec+0x12b/0x1c0
btrfs_rm_device+0x127/0x610
btrfs_ioctl+0x2a31/0x2e70
__x64_sys_ioctl+0x80/0xb0
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
-> #2 (sb_writers#12){.+.+}-{0:0}:
lo_write_bvec+0xc2/0x240 [loop]
loop_process_work+0x238/0xd00 [loop]
process_one_work+0x26b/0x560
worker_thread+0x55/0x3c0
kthread+0x140/0x160
ret_from_fork+0x1f/0x30
-> #1 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}:
process_one_work+0x245/0x560
worker_thread+0x55/0x3c0
kthread+0x140/0x160
ret_from_fork+0x1f/0x30
-> #0 ((wq_completion)loop0){+.+.}-{0:0}:
__lock_acquire+0x10ea/0x1d90
lock_acquire+0xb5/0x2b0
flush_workqueue+0x91/0x5e0
drain_workqueue+0xa0/0x110
destroy_workqueue+0x36/0x250
__loop_clr_fd+0x9a/0x660 [loop]
block_ioctl+0x3f/0x50
__x64_sys_ioctl+0x80/0xb0
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
other info that might help us debug this:
Chain exists of:
(wq_completion)loop0 --> &disk->open_mutex --> &lo->lo_mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&lo->lo_mutex);
lock(&disk->open_mutex);
lock(&lo->lo_mutex);
lock((wq_completion)loop0);
*** DEADLOCK ***
1 lock held by losetup/11576:
#0: ffff9bbe88e4fc68 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x41/0x660 [loop]
stack backtrace:
CPU: 0 PID: 11576 Comm: losetup Not tainted 5.14.0-rc2+ #405
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
Call Trace:
dump_stack_lvl+0x57/0x72
check_noncircular+0xcf/0xf0
? stack_trace_save+0x3b/0x50
__lock_acquire+0x10ea/0x1d90
lock_acquire+0xb5/0x2b0
? flush_workqueue+0x67/0x5e0
? lockdep_init_map_type+0x47/0x220
flush_workqueue+0x91/0x5e0
? flush_workqueue+0x67/0x5e0
? verify_cpu+0xf0/0x100
drain_workqueue+0xa0/0x110
destroy_workqueue+0x36/0x250
__loop_clr_fd+0x9a/0x660 [loop]
? blkdev_ioctl+0x8d/0x2a0
block_ioctl+0x3f/0x50
__x64_sys_ioctl+0x80/0xb0
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f31b02404cb
Instead what we want to do is populate our device lookup args before we
grab any locks, and then pass these args into btrfs_rm_device(). From
there we can find the device and do the appropriate removal.
Suggested-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We are going to want to populate our device lookup args outside of any
locks and then do the actual device lookup later, so add a helper to do
this work and make btrfs_find_device_by_devspec() use this helper for
now.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have a lot of device lookup functions that all do something slightly
different. Clean this up by adding a struct to hold the different
lookup criteria, and then pass this around to btrfs_find_device() so it
can do the proper matching based on the lookup criteria.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's a subtle case where if we're removing the seed device from a
file system we need to free its private copy of the fs_devices. However
we do not need to call close_fs_devices(), because at this point there
are no devices left to close as we've closed the last one. The only
thing that close_fs_devices() does is decrement ->opened, which should
be 1. We want to avoid calling close_fs_devices() here because it has a
lockdep_assert_held(&uuid_mutex), and we are going to stop holding the
uuid_mutex in this path.
So simply decrement the ->opened counter like we should, and then clean
up like normal. Also add a comment explaining what we're doing here as
I initially removed this code erroneously.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
A bug was was checking a wrong device count before we delete the struct
btrfs_fs_devices in btrfs_rm_device(). To avoid future confusion and
easy reference add a comment about the various device counts that we have
in the struct btrfs_fs_devices.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For both sprout and seed fsids,
btrfs_fs_devices::num_devices provides device count including missing
btrfs_fs_devices::open_devices provides device count excluding missing
We create a dummy struct btrfs_device for the missing device, so
num_devices != open_devices when there is a missing device.
In btrfs_rm_devices() we wrongly check for %cur_devices->open_devices
before freeing the seed fs_devices. Instead we should check for
%cur_devices->num_devices.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At replay_dir_deletes(), if find_dir_range() returns an error we break out
of the main while loop and then assign a value of 0 (success) to the 'ret'
variable, resulting in completely ignoring that an error happened. Fix
that by jumping to the 'out' label when find_dir_range() returns an error
(negative value).
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The member btrfs_bio::logical is only initialized by two call sites:
- btrfs_repair_one_sector()
No corresponding site to utilize it.
- btrfs_submit_direct()
The corresponding site to utilize it is btrfs_check_read_dio_bio().
However for btrfs_check_read_dio_bio(), we can grab the file_offset from
btrfs_dio_private::file_offset directly.
Thus it turns out we don't really need that btrfs_bio::logical member at
all.
For btrfs_bio, the logical bytenr can be fetched from its
bio->bi_iter.bi_sector directly.
So let's just remove the member to save 8 bytes for structure btrfs_bio.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The naming of "logical_offset" can be confused with logical bytenr of
the dio range.
In fact it's file offset, and the naming "file_offset" is already widely
used in all other sites.
Just do the rename to avoid confusion.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_update_block_group() accounts for the number of bytes allocated or
freed. Argument @alloc specifies whether the call is for alloc or free.
Convert the argument @alloc type from int to bool.
Reviewed-by: Su Yue <l@damenly.su>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that real_root is only used in ref-verify core gate it behind
CONFIG_BTRFS_FS_REF_VERIFY ifdef. This shrinks the size of pending
delayed refs by 8 bytes per ref, of which we can have many at any one
time depending on intensity of the workload. Also change the comment
about the member as it no longer deals with qgroups.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of checking whether qgroup processing for a dealyed ref has to
happen in the core of delayed ref, simply pull the check at init time of
respective delayed ref structures. This eliminates the final use of
real_root in delayed-ref core paving the way to making this member
optional.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In order to make 'real_root' used only in ref-verify it's required to
have the necessary context to perform the same checks that this member
is used for. So add 'mod_root' which will contain the root on behalf of
which a delayed ref was created and a 'skip_group' parameter which
will contain callsite-specific override of skip_qgroup.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The real_root field is going to be used only by ref-verify tool so limit
its use outside of it. Blocks belonging to the chunk root will always
have it as an owner so the check is equivalent.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
