* [PATCH AUTOSEL 6.6 1/6] misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle
@ 2024-12-04 22:24 Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 2/6] rtc: cmos: avoid taking rtc_lock for extended period of time Sasha Levin
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: Sasha Levin @ 2024-12-04 22:24 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Parker Newman, Andy Shevchenko, Greg Kroah-Hartman, Sasha Levin
From: Parker Newman <pnewman@connecttech.com>
[ Upstream commit 7738a7ab9d12c5371ed97114ee2132d4512e9fd5 ]
Add a quirk similar to eeprom_93xx46 to add an extra clock cycle before
reading data from the EEPROM.
The 93Cx6 family of EEPROMs output a "dummy 0 bit" between the writing
of the op-code/address from the host to the EEPROM and the reading of
the actual data from the EEPROM.
More info can be found on page 6 of the AT93C46 datasheet (linked below).
Similar notes are found in other 93xx6 datasheets.
In summary the read operation for a 93Cx6 EEPROM is:
Write to EEPROM: 110[A5-A0] (9 bits)
Read from EEPROM: 0[D15-D0] (17 bits)
Where:
110 is the start bit and READ OpCode
[A5-A0] is the address to read from
0 is a "dummy bit" preceding the actual data
[D15-D0] is the actual data.
Looking at the READ timing diagrams in the 93Cx6 datasheets the dummy
bit should be clocked out on the last address bit clock cycle meaning it
should be discarded naturally.
However, depending on the hardware configuration sometimes this dummy
bit is not discarded. This is the case with Exar PCI UARTs which require
an extra clock cycle between sending the address and reading the data.
Datasheet: https://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-5193-SEEPROM-AT93C46D-Datasheet.pdf
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Parker Newman <pnewman@connecttech.com>
Link: https://lore.kernel.org/r/0f23973efefccd2544705a0480b4ad4c2353e407.1727880931.git.pnewman@connecttech.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/misc/eeprom/eeprom_93cx6.c | 10 ++++++++++
include/linux/eeprom_93cx6.h | 11 +++++++++++
2 files changed, 21 insertions(+)
diff --git a/drivers/misc/eeprom/eeprom_93cx6.c b/drivers/misc/eeprom/eeprom_93cx6.c
index 9627294fe3e95..4c9827fe92173 100644
--- a/drivers/misc/eeprom/eeprom_93cx6.c
+++ b/drivers/misc/eeprom/eeprom_93cx6.c
@@ -186,6 +186,11 @@ void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word,
eeprom_93cx6_write_bits(eeprom, command,
PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
+ if (has_quirk_extra_read_cycle(eeprom)) {
+ eeprom_93cx6_pulse_high(eeprom);
+ eeprom_93cx6_pulse_low(eeprom);
+ }
+
/*
* Read the requested 16 bits.
*/
@@ -252,6 +257,11 @@ void eeprom_93cx6_readb(struct eeprom_93cx6 *eeprom, const u8 byte,
eeprom_93cx6_write_bits(eeprom, command,
PCI_EEPROM_WIDTH_OPCODE + eeprom->width + 1);
+ if (has_quirk_extra_read_cycle(eeprom)) {
+ eeprom_93cx6_pulse_high(eeprom);
+ eeprom_93cx6_pulse_low(eeprom);
+ }
+
/*
* Read the requested 8 bits.
*/
diff --git a/include/linux/eeprom_93cx6.h b/include/linux/eeprom_93cx6.h
index c860c72a921d0..3a485cc0e0fa0 100644
--- a/include/linux/eeprom_93cx6.h
+++ b/include/linux/eeprom_93cx6.h
@@ -11,6 +11,8 @@
Supported chipsets: 93c46, 93c56 and 93c66.
*/
+#include <linux/bits.h>
+
/*
* EEPROM operation defines.
*/
@@ -34,6 +36,7 @@
* @register_write(struct eeprom_93cx6 *eeprom): handler to
* write to the eeprom register by using all reg_* fields.
* @width: eeprom width, should be one of the PCI_EEPROM_WIDTH_* defines
+ * @quirks: eeprom or controller quirks
* @drive_data: Set if we're driving the data line.
* @reg_data_in: register field to indicate data input
* @reg_data_out: register field to indicate data output
@@ -50,6 +53,9 @@ struct eeprom_93cx6 {
void (*register_write)(struct eeprom_93cx6 *eeprom);
int width;
+ unsigned int quirks;
+/* Some EEPROMs require an extra clock cycle before reading */
+#define PCI_EEPROM_QUIRK_EXTRA_READ_CYCLE BIT(0)
char drive_data;
char reg_data_in;
@@ -71,3 +77,8 @@ extern void eeprom_93cx6_wren(struct eeprom_93cx6 *eeprom, bool enable);
extern void eeprom_93cx6_write(struct eeprom_93cx6 *eeprom,
u8 addr, u16 data);
+
+static inline bool has_quirk_extra_read_cycle(struct eeprom_93cx6 *eeprom)
+{
+ return eeprom->quirks & PCI_EEPROM_QUIRK_EXTRA_READ_CYCLE;
+}
--
2.43.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH AUTOSEL 6.6 2/6] rtc: cmos: avoid taking rtc_lock for extended period of time
2024-12-04 22:24 [PATCH AUTOSEL 6.6 1/6] misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle Sasha Levin
@ 2024-12-04 22:24 ` Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 3/6] serial: 8250_dw: Add Sophgo SG2044 quirk Sasha Levin
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Sasha Levin @ 2024-12-04 22:24 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Dmitry Torokhov, Mateusz Jończyk, Alexandre Belloni,
Sasha Levin, linux-rtc
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
[ Upstream commit 0a6efab33eab4e973db26d9f90c3e97a7a82e399 ]
On my device reading entirety of /sys/devices/pnp0/00:03/cmos_nvram0/nvmem
takes about 9 msec during which time interrupts are off on the CPU that
does the read and the thread that performs the read can not be migrated
or preempted by another higher priority thread (RT or not).
Allow readers and writers be preempted by taking and releasing rtc_lock
spinlock for each individual byte read or written rather than once per
read/write request.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Link: https://lore.kernel.org/r/Zxv8QWR21AV4ztC5@google.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/rtc/rtc-cmos.c | 31 +++++++++++++++----------------
1 file changed, 15 insertions(+), 16 deletions(-)
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 35dca2accbb8d..5849d2970bba4 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -645,18 +645,17 @@ static int cmos_nvram_read(void *priv, unsigned int off, void *val,
unsigned char *buf = val;
off += NVRAM_OFFSET;
- spin_lock_irq(&rtc_lock);
- for (; count; count--, off++) {
+ for (; count; count--, off++, buf++) {
+ guard(spinlock_irq)(&rtc_lock);
if (off < 128)
- *buf++ = CMOS_READ(off);
+ *buf = CMOS_READ(off);
else if (can_bank2)
- *buf++ = cmos_read_bank2(off);
+ *buf = cmos_read_bank2(off);
else
- break;
+ return -EIO;
}
- spin_unlock_irq(&rtc_lock);
- return count ? -EIO : 0;
+ return 0;
}
static int cmos_nvram_write(void *priv, unsigned int off, void *val,
@@ -671,23 +670,23 @@ static int cmos_nvram_write(void *priv, unsigned int off, void *val,
* NVRAM to update, updating checksums is also part of its job.
*/
off += NVRAM_OFFSET;
- spin_lock_irq(&rtc_lock);
- for (; count; count--, off++) {
+ for (; count; count--, off++, buf++) {
/* don't trash RTC registers */
if (off == cmos->day_alrm
|| off == cmos->mon_alrm
|| off == cmos->century)
- buf++;
- else if (off < 128)
- CMOS_WRITE(*buf++, off);
+ continue;
+
+ guard(spinlock_irq)(&rtc_lock);
+ if (off < 128)
+ CMOS_WRITE(*buf, off);
else if (can_bank2)
- cmos_write_bank2(*buf++, off);
+ cmos_write_bank2(*buf, off);
else
- break;
+ return -EIO;
}
- spin_unlock_irq(&rtc_lock);
- return count ? -EIO : 0;
+ return 0;
}
/*----------------------------------------------------------------*/
--
2.43.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH AUTOSEL 6.6 3/6] serial: 8250_dw: Add Sophgo SG2044 quirk
2024-12-04 22:24 [PATCH AUTOSEL 6.6 1/6] misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 2/6] rtc: cmos: avoid taking rtc_lock for extended period of time Sasha Levin
@ 2024-12-04 22:24 ` Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 4/6] smb: client: don't try following DFS links in cifs_tree_connect() Sasha Levin
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Sasha Levin @ 2024-12-04 22:24 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Inochi Amaoto, Andy Shevchenko, Ilpo Järvinen,
Greg Kroah-Hartman, Sasha Levin, jirislaby, unicorn_wang,
inochiama, linux-serial
From: Inochi Amaoto <inochiama@gmail.com>
[ Upstream commit cad4dda82c7eedcfc22597267e710ccbcf39d572 ]
SG2044 relys on an internal divisor when calculating bitrate, which
means a wrong clock for the most common bitrates. So add a quirk for
this uart device to skip the set rate call and only relys on the
internal UART divisor.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Inochi Amaoto <inochiama@gmail.com>
Link: https://lore.kernel.org/r/20241024062105.782330-4-inochiama@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/tty/serial/8250/8250_dw.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 8aed33be2ebf4..eaf4a907380aa 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -785,7 +785,7 @@ static const struct dw8250_platform_data dw8250_renesas_rzn1_data = {
.quirks = DW_UART_QUIRK_CPR_VALUE | DW_UART_QUIRK_IS_DMA_FC,
};
-static const struct dw8250_platform_data dw8250_starfive_jh7100_data = {
+static const struct dw8250_platform_data dw8250_skip_set_rate_data = {
.usr_reg = DW_UART_USR,
.quirks = DW_UART_QUIRK_SKIP_SET_RATE,
};
@@ -795,7 +795,8 @@ static const struct of_device_id dw8250_of_match[] = {
{ .compatible = "cavium,octeon-3860-uart", .data = &dw8250_octeon_3860_data },
{ .compatible = "marvell,armada-38x-uart", .data = &dw8250_armada_38x_data },
{ .compatible = "renesas,rzn1-uart", .data = &dw8250_renesas_rzn1_data },
- { .compatible = "starfive,jh7100-uart", .data = &dw8250_starfive_jh7100_data },
+ { .compatible = "sophgo,sg2044-uart", .data = &dw8250_skip_set_rate_data },
+ { .compatible = "starfive,jh7100-uart", .data = &dw8250_skip_set_rate_data },
{ /* Sentinel */ }
};
MODULE_DEVICE_TABLE(of, dw8250_of_match);
--
2.43.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH AUTOSEL 6.6 4/6] smb: client: don't try following DFS links in cifs_tree_connect()
2024-12-04 22:24 [PATCH AUTOSEL 6.6 1/6] misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 2/6] rtc: cmos: avoid taking rtc_lock for extended period of time Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 3/6] serial: 8250_dw: Add Sophgo SG2044 quirk Sasha Levin
@ 2024-12-04 22:24 ` Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 5/6] setlocalversion: work around "git describe" performance Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 6/6] io_uring/tctx: work around xa_store() allocation error issue Sasha Levin
4 siblings, 0 replies; 6+ messages in thread
From: Sasha Levin @ 2024-12-04 22:24 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Paulo Alcantara, Steve French, Sasha Levin, sfrench, linux-cifs,
samba-technical
From: Paulo Alcantara <pc@manguebit.com>
[ Upstream commit 36008fe6e3dc588e5e9ceae6e82c7f69399eb5d8 ]
We can't properly support chasing DFS links in cifs_tree_connect()
because
(1) We don't support creating new sessions while we're reconnecting,
which would be required for DFS interlinks.
(2) ->is_path_accessible() can't be called from cifs_tree_connect()
as it would deadlock with smb2_reconnect(). This is required for
checking if new DFS target is a nested DFS link.
By unconditionally trying to get an DFS referral from new DFS target
isn't correct because if the new DFS target (interlink) is an DFS
standalone namespace, then we would end up getting -ELOOP and then
potentially leaving tcon disconnected.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/smb/client/dfs.c | 188 ++++----------------------------------------
1 file changed, 17 insertions(+), 171 deletions(-)
diff --git a/fs/smb/client/dfs.c b/fs/smb/client/dfs.c
index 3ec965547e3d4..bd259b04cdede 100644
--- a/fs/smb/client/dfs.c
+++ b/fs/smb/client/dfs.c
@@ -324,49 +324,6 @@ int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx, bool *isdfs)
return rc;
}
-/* Update dfs referral path of superblock */
-static int update_server_fullpath(struct TCP_Server_Info *server, struct cifs_sb_info *cifs_sb,
- const char *target)
-{
- int rc = 0;
- size_t len = strlen(target);
- char *refpath, *npath;
-
- if (unlikely(len < 2 || *target != '\\'))
- return -EINVAL;
-
- if (target[1] == '\\') {
- len += 1;
- refpath = kmalloc(len, GFP_KERNEL);
- if (!refpath)
- return -ENOMEM;
-
- scnprintf(refpath, len, "%s", target);
- } else {
- len += sizeof("\\");
- refpath = kmalloc(len, GFP_KERNEL);
- if (!refpath)
- return -ENOMEM;
-
- scnprintf(refpath, len, "\\%s", target);
- }
-
- npath = dfs_cache_canonical_path(refpath, cifs_sb->local_nls, cifs_remap(cifs_sb));
- kfree(refpath);
-
- if (IS_ERR(npath)) {
- rc = PTR_ERR(npath);
- } else {
- mutex_lock(&server->refpath_lock);
- spin_lock(&server->srv_lock);
- kfree(server->leaf_fullpath);
- server->leaf_fullpath = npath;
- spin_unlock(&server->srv_lock);
- mutex_unlock(&server->refpath_lock);
- }
- return rc;
-}
-
static int target_share_matches_server(struct TCP_Server_Info *server, char *share,
bool *target_match)
{
@@ -391,77 +348,22 @@ static int target_share_matches_server(struct TCP_Server_Info *server, char *sha
return rc;
}
-static void __tree_connect_ipc(const unsigned int xid, char *tree,
- struct cifs_sb_info *cifs_sb,
- struct cifs_ses *ses)
-{
- struct TCP_Server_Info *server = ses->server;
- struct cifs_tcon *tcon = ses->tcon_ipc;
- int rc;
-
- spin_lock(&ses->ses_lock);
- spin_lock(&ses->chan_lock);
- if (cifs_chan_needs_reconnect(ses, server) ||
- ses->ses_status != SES_GOOD) {
- spin_unlock(&ses->chan_lock);
- spin_unlock(&ses->ses_lock);
- cifs_server_dbg(FYI, "%s: skipping ipc reconnect due to disconnected ses\n",
- __func__);
- return;
- }
- spin_unlock(&ses->chan_lock);
- spin_unlock(&ses->ses_lock);
-
- cifs_server_lock(server);
- scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", server->hostname);
- cifs_server_unlock(server);
-
- rc = server->ops->tree_connect(xid, ses, tree, tcon,
- cifs_sb->local_nls);
- cifs_server_dbg(FYI, "%s: tree_reconnect %s: %d\n", __func__, tree, rc);
- spin_lock(&tcon->tc_lock);
- if (rc) {
- tcon->status = TID_NEED_TCON;
- } else {
- tcon->status = TID_GOOD;
- tcon->need_reconnect = false;
- }
- spin_unlock(&tcon->tc_lock);
-}
-
-static void tree_connect_ipc(const unsigned int xid, char *tree,
- struct cifs_sb_info *cifs_sb,
- struct cifs_tcon *tcon)
-{
- struct cifs_ses *ses = tcon->ses;
-
- __tree_connect_ipc(xid, tree, cifs_sb, ses);
- __tree_connect_ipc(xid, tree, cifs_sb, CIFS_DFS_ROOT_SES(ses));
-}
-
-static int __tree_connect_dfs_target(const unsigned int xid, struct cifs_tcon *tcon,
- struct cifs_sb_info *cifs_sb, char *tree, bool islink,
- struct dfs_cache_tgt_list *tl)
+static int tree_connect_dfs_target(const unsigned int xid,
+ struct cifs_tcon *tcon,
+ struct cifs_sb_info *cifs_sb,
+ char *tree, bool islink,
+ struct dfs_cache_tgt_list *tl)
{
- int rc;
+ const struct smb_version_operations *ops = tcon->ses->server->ops;
struct TCP_Server_Info *server = tcon->ses->server;
- const struct smb_version_operations *ops = server->ops;
- struct cifs_ses *root_ses = CIFS_DFS_ROOT_SES(tcon->ses);
- char *share = NULL, *prefix = NULL;
struct dfs_cache_tgt_iterator *tit;
+ char *share = NULL, *prefix = NULL;
bool target_match;
-
- tit = dfs_cache_get_tgt_iterator(tl);
- if (!tit) {
- rc = -ENOENT;
- goto out;
- }
+ int rc = -ENOENT;
/* Try to tree connect to all dfs targets */
- for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
- const char *target = dfs_cache_get_tgt_name(tit);
- DFS_CACHE_TGT_LIST(ntl);
-
+ for (tit = dfs_cache_get_tgt_iterator(tl);
+ tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
kfree(share);
kfree(prefix);
share = prefix = NULL;
@@ -482,69 +384,16 @@ static int __tree_connect_dfs_target(const unsigned int xid, struct cifs_tcon *t
}
dfs_cache_noreq_update_tgthint(server->leaf_fullpath + 1, tit);
- tree_connect_ipc(xid, tree, cifs_sb, tcon);
-
scnprintf(tree, MAX_TREE_SIZE, "\\%s", share);
- if (!islink) {
- rc = ops->tree_connect(xid, tcon->ses, tree, tcon, cifs_sb->local_nls);
- break;
- }
-
- /*
- * If no dfs referrals were returned from link target, then just do a TREE_CONNECT
- * to it. Otherwise, cache the dfs referral and then mark current tcp ses for
- * reconnect so either the demultiplex thread or the echo worker will reconnect to
- * newly resolved target.
- */
- if (dfs_cache_find(xid, root_ses, cifs_sb->local_nls, cifs_remap(cifs_sb), target,
- NULL, &ntl)) {
- rc = ops->tree_connect(xid, tcon->ses, tree, tcon, cifs_sb->local_nls);
- if (rc)
- continue;
-
+ rc = ops->tree_connect(xid, tcon->ses, tree,
+ tcon, tcon->ses->local_nls);
+ if (islink && !rc && cifs_sb)
rc = cifs_update_super_prepath(cifs_sb, prefix);
- } else {
- /* Target is another dfs share */
- rc = update_server_fullpath(server, cifs_sb, target);
- dfs_cache_free_tgts(tl);
-
- if (!rc) {
- rc = -EREMOTE;
- list_replace_init(&ntl.tl_list, &tl->tl_list);
- } else
- dfs_cache_free_tgts(&ntl);
- }
break;
}
-out:
kfree(share);
kfree(prefix);
-
- return rc;
-}
-
-static int tree_connect_dfs_target(const unsigned int xid, struct cifs_tcon *tcon,
- struct cifs_sb_info *cifs_sb, char *tree, bool islink,
- struct dfs_cache_tgt_list *tl)
-{
- int rc;
- int num_links = 0;
- struct TCP_Server_Info *server = tcon->ses->server;
- char *old_fullpath = server->leaf_fullpath;
-
- do {
- rc = __tree_connect_dfs_target(xid, tcon, cifs_sb, tree, islink, tl);
- if (!rc || rc != -EREMOTE)
- break;
- } while (rc = -ELOOP, ++num_links < MAX_NESTED_LINKS);
- /*
- * If we couldn't tree connect to any targets from last referral path, then
- * retry it from newly resolved dfs referral.
- */
- if (rc && server->leaf_fullpath != old_fullpath)
- cifs_signal_cifsd_for_reconnect(server, true);
-
dfs_cache_free_tgts(tl);
return rc;
}
@@ -599,14 +448,11 @@ int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const stru
if (!IS_ERR(sb))
cifs_sb = CIFS_SB(sb);
- /*
- * Tree connect to last share in @tcon->tree_name whether dfs super or
- * cached dfs referral was not found.
- */
- if (!cifs_sb || !server->leaf_fullpath ||
+ /* Tree connect to last share in @tcon->tree_name if no DFS referral */
+ if (!server->leaf_fullpath ||
dfs_cache_noreq_find(server->leaf_fullpath + 1, &ref, &tl)) {
- rc = ops->tree_connect(xid, tcon->ses, tcon->tree_name, tcon,
- cifs_sb ? cifs_sb->local_nls : nlsc);
+ rc = ops->tree_connect(xid, tcon->ses, tcon->tree_name,
+ tcon, tcon->ses->local_nls);
goto out;
}
--
2.43.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH AUTOSEL 6.6 5/6] setlocalversion: work around "git describe" performance
2024-12-04 22:24 [PATCH AUTOSEL 6.6 1/6] misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle Sasha Levin
` (2 preceding siblings ...)
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 4/6] smb: client: don't try following DFS links in cifs_tree_connect() Sasha Levin
@ 2024-12-04 22:24 ` Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 6/6] io_uring/tctx: work around xa_store() allocation error issue Sasha Levin
4 siblings, 0 replies; 6+ messages in thread
From: Sasha Levin @ 2024-12-04 22:24 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Rasmus Villemoes, Sean Christopherson, Josh Poimboeuf,
Masahiro Yamada, Sasha Levin
From: Rasmus Villemoes <linux@rasmusvillemoes.dk>
[ Upstream commit 523f3dbc187a9618d4fd80c2b438e4d490705dcd ]
Contrary to expectations, passing a single candidate tag to "git
describe" is slower than not passing any --match options.
$ time git describe --debug
...
traversed 10619 commits
...
v6.12-rc5-63-g0fc810ae3ae1
real 0m0.169s
$ time git describe --match=v6.12-rc5 --debug
...
traversed 1310024 commits
v6.12-rc5-63-g0fc810ae3ae1
real 0m1.281s
In fact, the --debug output shows that git traverses all or most of
history. For some repositories and/or git versions, those 1.3s are
actually 10-15 seconds.
This has been acknowledged as a performance bug in git [1], and a fix
is on its way [2]. However, no solution is yet in git.git, and even
when one lands, it will take quite a while before it finds its way to
a release and for $random_kernel_developer to pick that up.
So rewrite the logic to use plumbing commands. For each of the
candidate values of $tag, we ask: (1) is $tag even an annotated
tag? (2) Is it eligible to describe HEAD, i.e. an ancestor of
HEAD? (3) If so, how many commits are in $tag..HEAD?
I have tested that this produces the same output as the current script
for ~700 random commits between v6.9..v6.10. For those 700 commits,
and in my git repo, the 'make -s kernelrelease' command is on average
~4 times faster with this patch applied (geometric mean of ratios).
For the commit mentioned in Josh's original report [3], the
time-consuming part of setlocalversion goes from
$ time git describe --match=v6.12-rc5 c1e939a21eb1
v6.12-rc5-44-gc1e939a21eb1
real 0m1.210s
to
$ time git rev-list --count --left-right v6.12-rc5..c1e939a21eb1
0 44
real 0m0.037s
[1] https://lore.kernel.org/git/20241101113910.GA2301440@coredump.intra.peff.net/
[2] https://lore.kernel.org/git/20241106192236.GC880133@coredump.intra.peff.net/
[3] https://lore.kernel.org/lkml/309549cafdcfe50c4fceac3263220cc3d8b109b2.1730337435.git.jpoimboe@kernel.org/
Reported-by: Sean Christopherson <seanjc@google.com>
Closes: https://lore.kernel.org/lkml/ZPtlxmdIJXOe0sEy@google.com/
Reported-by: Josh Poimboeuf <jpoimboe@kernel.org>
Closes: https://lore.kernel.org/lkml/309549cafdcfe50c4fceac3263220cc3d8b109b2.1730337435.git.jpoimboe@kernel.org/
Tested-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
scripts/setlocalversion | 54 +++++++++++++++++++++++++++++------------
1 file changed, 38 insertions(+), 16 deletions(-)
diff --git a/scripts/setlocalversion b/scripts/setlocalversion
index 38b96c6797f40..5818465abba98 100755
--- a/scripts/setlocalversion
+++ b/scripts/setlocalversion
@@ -30,6 +30,27 @@ if test $# -gt 0 -o ! -d "$srctree"; then
usage
fi
+try_tag() {
+ tag="$1"
+
+ # Is $tag an annotated tag?
+ [ "$(git cat-file -t "$tag" 2> /dev/null)" = tag ] || return 1
+
+ # Is it an ancestor of HEAD, and if so, how many commits are in $tag..HEAD?
+ # shellcheck disable=SC2046 # word splitting is the point here
+ set -- $(git rev-list --count --left-right "$tag"...HEAD 2> /dev/null)
+
+ # $1 is 0 if and only if $tag is an ancestor of HEAD. Use
+ # string comparison, because $1 is empty if the 'git rev-list'
+ # command somehow failed.
+ [ "$1" = 0 ] || return 1
+
+ # $2 is the number of commits in the range $tag..HEAD, possibly 0.
+ count="$2"
+
+ return 0
+}
+
scm_version()
{
local short=false
@@ -61,33 +82,33 @@ scm_version()
# stable kernel: 6.1.7 -> v6.1.7
version_tag=v$(echo "${KERNELVERSION}" | sed -E 's/^([0-9]+\.[0-9]+)\.0(.*)$/\1\2/')
+ # try_tag initializes count if the tag is usable.
+ count=
+
# If a localversion* file exists, and the corresponding
# annotated tag exists and is an ancestor of HEAD, use
# it. This is the case in linux-next.
- tag=${file_localversion#-}
- desc=
- if [ -n "${tag}" ]; then
- desc=$(git describe --match=$tag 2>/dev/null)
+ if [ -n "${file_localversion#-}" ] ; then
+ try_tag "${file_localversion#-}"
fi
# Otherwise, if a localversion* file exists, and the tag
# obtained by appending it to the tag derived from
# KERNELVERSION exists and is an ancestor of HEAD, use
# it. This is e.g. the case in linux-rt.
- if [ -z "${desc}" ] && [ -n "${file_localversion}" ]; then
- tag="${version_tag}${file_localversion}"
- desc=$(git describe --match=$tag 2>/dev/null)
+ if [ -z "${count}" ] && [ -n "${file_localversion}" ]; then
+ try_tag "${version_tag}${file_localversion}"
fi
# Otherwise, default to the annotated tag derived from KERNELVERSION.
- if [ -z "${desc}" ]; then
- tag="${version_tag}"
- desc=$(git describe --match=$tag 2>/dev/null)
+ if [ -z "${count}" ]; then
+ try_tag "${version_tag}"
fi
- # If we are at the tagged commit, we ignore it because the version is
- # well-defined.
- if [ "${tag}" != "${desc}" ]; then
+ # If we are at the tagged commit, we ignore it because the
+ # version is well-defined. If none of the attempted tags exist
+ # or were usable, $count is still empty.
+ if [ -z "${count}" ] || [ "${count}" -gt 0 ]; then
# If only the short version is requested, don't bother
# running further git commands
@@ -95,14 +116,15 @@ scm_version()
echo "+"
return
fi
+
# If we are past the tagged commit, we pretty print it.
# (like 6.1.0-14595-g292a089d78d3)
- if [ -n "${desc}" ]; then
- echo "${desc}" | awk -F- '{printf("-%05d", $(NF-1))}'
+ if [ -n "${count}" ]; then
+ printf "%s%05d" "-" "${count}"
fi
# Add -g and exactly 12 hex chars.
- printf '%s%s' -g "$(echo $head | cut -c1-12)"
+ printf '%s%.12s' -g "$head"
fi
if ${no_dirty}; then
--
2.43.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH AUTOSEL 6.6 6/6] io_uring/tctx: work around xa_store() allocation error issue
2024-12-04 22:24 [PATCH AUTOSEL 6.6 1/6] misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle Sasha Levin
` (3 preceding siblings ...)
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 5/6] setlocalversion: work around "git describe" performance Sasha Levin
@ 2024-12-04 22:24 ` Sasha Levin
4 siblings, 0 replies; 6+ messages in thread
From: Sasha Levin @ 2024-12-04 22:24 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Jens Axboe, syzbot+cc36d44ec9f368e443d3, Sasha Levin,
asml.silence, io-uring
From: Jens Axboe <axboe@kernel.dk>
[ Upstream commit 7eb75ce7527129d7f1fee6951566af409a37a1c4 ]
syzbot triggered the following WARN_ON:
WARNING: CPU: 0 PID: 16 at io_uring/tctx.c:51 __io_uring_free+0xfa/0x140 io_uring/tctx.c:51
which is the
WARN_ON_ONCE(!xa_empty(&tctx->xa));
sanity check in __io_uring_free() when a io_uring_task is going through
its final put. The syzbot test case includes injecting memory allocation
failures, and it very much looks like xa_store() can fail one of its
memory allocations and end up with ->head being non-NULL even though no
entries exist in the xarray.
Until this issue gets sorted out, work around it by attempting to
iterate entries in our xarray, and WARN_ON_ONCE() if one is found.
Reported-by: syzbot+cc36d44ec9f368e443d3@syzkaller.appspotmail.com
Link: https://lore.kernel.org/io-uring/673c1643.050a0220.87769.0066.GAE@google.com/
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
io_uring/tctx.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/io_uring/tctx.c b/io_uring/tctx.c
index c043fe93a3f23..84f6a83857204 100644
--- a/io_uring/tctx.c
+++ b/io_uring/tctx.c
@@ -47,8 +47,19 @@ static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
void __io_uring_free(struct task_struct *tsk)
{
struct io_uring_task *tctx = tsk->io_uring;
+ struct io_tctx_node *node;
+ unsigned long index;
- WARN_ON_ONCE(!xa_empty(&tctx->xa));
+ /*
+ * Fault injection forcing allocation errors in the xa_store() path
+ * can lead to xa_empty() returning false, even though no actual
+ * node is stored in the xarray. Until that gets sorted out, attempt
+ * an iteration here and warn if any entries are found.
+ */
+ xa_for_each(&tctx->xa, index, node) {
+ WARN_ON_ONCE(1);
+ break;
+ }
WARN_ON_ONCE(tctx->io_wq);
WARN_ON_ONCE(tctx->cached_refs);
--
2.43.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2024-12-04 23:35 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-12-04 22:24 [PATCH AUTOSEL 6.6 1/6] misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 2/6] rtc: cmos: avoid taking rtc_lock for extended period of time Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 3/6] serial: 8250_dw: Add Sophgo SG2044 quirk Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 4/6] smb: client: don't try following DFS links in cifs_tree_connect() Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 5/6] setlocalversion: work around "git describe" performance Sasha Levin
2024-12-04 22:24 ` [PATCH AUTOSEL 6.6 6/6] io_uring/tctx: work around xa_store() allocation error issue Sasha Levin
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox