From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: stable@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
patches@lists.linux.dev, Fedor Pchelkin <pchelkin@ispras.ru>,
Alexey Khoroshilov <khoroshilov@ispras.ru>,
Daniel Starke <daniel.starke@siemens.com>
Subject: [PATCH 5.10 82/92] Revert "tty: n_gsm: avoid call of sleeping functions from atomic context"
Date: Mon, 5 Dec 2022 20:10:35 +0100 [thread overview]
Message-ID: <20221205190806.179857803@linuxfoundation.org> (raw)
In-Reply-To: <20221205190803.464934752@linuxfoundation.org>
From: Fedor Pchelkin <pchelkin@ispras.ru>
commit acdab4cb4ba7e5f94d2b422ebd7bf4bf68178fb2 upstream.
This reverts commit 902e02ea9385373ce4b142576eef41c642703955.
The above commit is reverted as the usage of tx_mutex seems not to solve
the problem described in 902e02ea9385 ("tty: n_gsm: avoid call of sleeping
functions from atomic context") and just moves the bug to another place.
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Reviewed-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20221008110221.13645-2-pchelkin@ispras.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/tty/n_gsm.c | 39 +++++++++++++++++++++------------------
1 file changed, 21 insertions(+), 18 deletions(-)
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -235,7 +235,7 @@ struct gsm_mux {
int old_c_iflag; /* termios c_iflag value before attach */
bool constipated; /* Asked by remote to shut up */
- struct mutex tx_mutex;
+ spinlock_t tx_lock;
unsigned int tx_bytes; /* TX data outstanding */
#define TX_THRESH_HI 8192
#define TX_THRESH_LO 2048
@@ -820,14 +820,15 @@ static void __gsm_data_queue(struct gsm_
*
* Add data to the transmit queue and try and get stuff moving
* out of the mux tty if not already doing so. Take the
- * the gsm tx mutex and dlci lock.
+ * the gsm tx lock and dlci lock.
*/
static void gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg)
{
- mutex_lock(&dlci->gsm->tx_mutex);
+ unsigned long flags;
+ spin_lock_irqsave(&dlci->gsm->tx_lock, flags);
__gsm_data_queue(dlci, msg);
- mutex_unlock(&dlci->gsm->tx_mutex);
+ spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags);
}
/**
@@ -839,7 +840,7 @@ static void gsm_data_queue(struct gsm_dl
* is data. Keep to the MRU of the mux. This path handles the usual tty
* interface which is a byte stream with optional modem data.
*
- * Caller must hold the tx_mutex of the mux.
+ * Caller must hold the tx_lock of the mux.
*/
static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci)
@@ -902,7 +903,7 @@ static int gsm_dlci_data_output(struct g
* is data. Keep to the MRU of the mux. This path handles framed data
* queued as skbuffs to the DLCI.
*
- * Caller must hold the tx_mutex of the mux.
+ * Caller must hold the tx_lock of the mux.
*/
static int gsm_dlci_data_output_framed(struct gsm_mux *gsm,
@@ -918,7 +919,7 @@ static int gsm_dlci_data_output_framed(s
if (dlci->adaption == 4)
overhead = 1;
- /* dlci->skb is locked by tx_mutex */
+ /* dlci->skb is locked by tx_lock */
if (dlci->skb == NULL) {
dlci->skb = skb_dequeue_tail(&dlci->skb_list);
if (dlci->skb == NULL)
@@ -1018,12 +1019,13 @@ static void gsm_dlci_data_sweep(struct g
static void gsm_dlci_data_kick(struct gsm_dlci *dlci)
{
+ unsigned long flags;
int sweep;
if (dlci->constipated)
return;
- mutex_lock(&dlci->gsm->tx_mutex);
+ spin_lock_irqsave(&dlci->gsm->tx_lock, flags);
/* If we have nothing running then we need to fire up */
sweep = (dlci->gsm->tx_bytes < TX_THRESH_LO);
if (dlci->gsm->tx_bytes == 0) {
@@ -1034,7 +1036,7 @@ static void gsm_dlci_data_kick(struct gs
}
if (sweep)
gsm_dlci_data_sweep(dlci->gsm);
- mutex_unlock(&dlci->gsm->tx_mutex);
+ spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags);
}
/*
@@ -1256,6 +1258,7 @@ static void gsm_control_message(struct g
const u8 *data, int clen)
{
u8 buf[1];
+ unsigned long flags;
switch (command) {
case CMD_CLD: {
@@ -1277,9 +1280,9 @@ static void gsm_control_message(struct g
gsm->constipated = false;
gsm_control_reply(gsm, CMD_FCON, NULL, 0);
/* Kick the link in case it is idling */
- mutex_lock(&gsm->tx_mutex);
+ spin_lock_irqsave(&gsm->tx_lock, flags);
gsm_data_kick(gsm, NULL);
- mutex_unlock(&gsm->tx_mutex);
+ spin_unlock_irqrestore(&gsm->tx_lock, flags);
break;
case CMD_FCOFF:
/* Modem wants us to STFU */
@@ -2225,7 +2228,6 @@ static void gsm_free_mux(struct gsm_mux
break;
}
}
- mutex_destroy(&gsm->tx_mutex);
mutex_destroy(&gsm->mutex);
kfree(gsm->txframe);
kfree(gsm->buf);
@@ -2297,12 +2299,12 @@ static struct gsm_mux *gsm_alloc_mux(voi
}
spin_lock_init(&gsm->lock);
mutex_init(&gsm->mutex);
- mutex_init(&gsm->tx_mutex);
kref_init(&gsm->ref);
INIT_LIST_HEAD(&gsm->tx_list);
timer_setup(&gsm->t2_timer, gsm_control_retransmit, 0);
init_waitqueue_head(&gsm->event);
spin_lock_init(&gsm->control_lock);
+ spin_lock_init(&gsm->tx_lock);
gsm->t1 = T1;
gsm->t2 = T2;
@@ -2327,7 +2329,6 @@ static struct gsm_mux *gsm_alloc_mux(voi
}
spin_unlock(&gsm_mux_lock);
if (i == MAX_MUX) {
- mutex_destroy(&gsm->tx_mutex);
mutex_destroy(&gsm->mutex);
kfree(gsm->txframe);
kfree(gsm->buf);
@@ -2652,15 +2653,16 @@ static int gsmld_open(struct tty_struct
static void gsmld_write_wakeup(struct tty_struct *tty)
{
struct gsm_mux *gsm = tty->disc_data;
+ unsigned long flags;
/* Queue poll */
clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
- mutex_lock(&gsm->tx_mutex);
+ spin_lock_irqsave(&gsm->tx_lock, flags);
gsm_data_kick(gsm, NULL);
if (gsm->tx_bytes < TX_THRESH_LO) {
gsm_dlci_data_sweep(gsm);
}
- mutex_unlock(&gsm->tx_mutex);
+ spin_unlock_irqrestore(&gsm->tx_lock, flags);
}
/**
@@ -2703,6 +2705,7 @@ static ssize_t gsmld_write(struct tty_st
const unsigned char *buf, size_t nr)
{
struct gsm_mux *gsm = tty->disc_data;
+ unsigned long flags;
int space;
int ret;
@@ -2710,13 +2713,13 @@ static ssize_t gsmld_write(struct tty_st
return -ENODEV;
ret = -ENOBUFS;
- mutex_lock(&gsm->tx_mutex);
+ spin_lock_irqsave(&gsm->tx_lock, flags);
space = tty_write_room(tty);
if (space >= nr)
ret = tty->ops->write(tty, buf, nr);
else
set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
- mutex_unlock(&gsm->tx_mutex);
+ spin_unlock_irqrestore(&gsm->tx_lock, flags);
return ret;
}
next prev parent reply other threads:[~2022-12-05 19:36 UTC|newest]
Thread overview: 98+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-12-05 19:09 [PATCH 5.10 00/92] 5.10.158-rc1 review Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 01/92] btrfs: sink iterator parameter to btrfs_ioctl_logical_to_ino Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 02/92] btrfs: free btrfs_path before copying inodes to userspace Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 03/92] spi: spi-imx: Fix spi_bus_clk if requested clock is higher than input clock Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 04/92] btrfs: move QUOTA_ENABLED check to rescan_should_stop from btrfs_qgroup_rescan_worker Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 05/92] drm/display/dp_mst: Fix drm_dp_mst_add_affected_dsc_crtcs() return code Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 06/92] kbuild: fix -Wimplicit-function-declaration in license_is_gpl_compatible Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 07/92] drm/amdgpu: update drm_display_info correctly when the edid is read Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 08/92] drm/amdgpu: Partially revert "drm/amdgpu: update drm_display_info correctly when the edid is read" Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 09/92] btrfs: qgroup: fix sleep from invalid context bug in btrfs_qgroup_inherit() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 10/92] iio: health: afe4403: Fix oob read in afe4403_read_raw Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 11/92] iio: health: afe4404: Fix oob read in afe4404_[read|write]_raw Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 12/92] iio: light: rpr0521: add missing Kconfig dependencies Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 13/92] bpf, perf: Use subprog name when reporting subprog ksymbol Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 14/92] scripts/faddr2line: Fix regression in name resolution on ppc64le Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 15/92] ARM: at91: rm9200: fix usb device clock id Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 16/92] libbpf: Handle size overflow for ringbuf mmap Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 17/92] hwmon: (ltc2947) fix temperature scaling Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 18/92] hwmon: (ina3221) Fix shunt sum critical calculation Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 19/92] hwmon: (i5500_temp) fix missing pci_disable_device() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 20/92] hwmon: (ibmpex) Fix possible UAF when ibmpex_register_bmc() fails Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 21/92] bpf: Do not copy spin lock field from user in bpf_selem_alloc Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 22/92] of: property: decrement node refcount in of_fwnode_get_reference_args() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 23/92] ixgbevf: Fix resource leak in ixgbevf_init_module() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 24/92] i40e: Fix error handling in i40e_init_module() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 25/92] fm10k: Fix error handling in fm10k_init_module() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 26/92] iavf: remove redundant ret variable Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 27/92] iavf: Fix error handling in iavf_init_module() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 28/92] e100: switch from pci_ to dma_ API Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 29/92] e100: Fix possible use after free in e100_xmit_prepare Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 30/92] net/mlx5: Fix uninitialized variable bug in outlen_write() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 31/92] net/mlx5e: Fix use-after-free when reverting termination table Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 32/92] can: sja1000_isa: sja1000_isa_probe(): add missing free_sja1000dev() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 33/92] can: cc770: cc770_isa_probe(): add missing free_cc770dev() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 34/92] qlcnic: fix sleep-in-atomic-context bugs caused by msleep Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 35/92] aquantia: Do not purge addresses when setting the number of rings Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 36/92] wifi: cfg80211: fix buffer overflow in elem comparison Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 37/92] wifi: cfg80211: dont allow multi-BSSID in S1G Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 38/92] wifi: mac8021: fix possible oob access in ieee80211_get_rate_duration Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 39/92] net: phy: fix null-ptr-deref while probe() failed Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 40/92] net: net_netdev: Fix error handling in ntb_netdev_init_module() Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 41/92] net/9p: Fix a potential socket leak in p9_socket_open Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 42/92] net: ethernet: nixge: fix NULL dereference Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 43/92] dsa: lan9303: Correct stat name Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 44/92] tipc: re-fetch skb cb after tipc_msg_validate Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 45/92] net: hsr: Fix potential use-after-free Greg Kroah-Hartman
2022-12-05 19:09 ` [PATCH 5.10 46/92] afs: Fix fileserver probe RTT handling Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 47/92] net: tun: Fix use-after-free in tun_detach() Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 48/92] packet: do not set TP_STATUS_CSUM_VALID on CHECKSUM_COMPLETE Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 49/92] sctp: fix memory leak in sctp_stream_outq_migrate() Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 50/92] net: ethernet: renesas: ravb: Fix promiscuous mode after system resumed Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 51/92] hwmon: (coretemp) Check for null before removing sysfs attrs Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 52/92] hwmon: (coretemp) fix pci device refcount leak in nv1a_ram_new() Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 53/92] net/mlx5: DR, Fix uninitialized var warning Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 54/92] riscv: vdso: fix section overlapping under some conditions Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 55/92] error-injection: Add prompt for function error injection Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 56/92] tools/vm/slabinfo-gnuplot: use "grep -E" instead of "egrep" Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 57/92] nilfs2: fix NULL pointer dereference in nilfs_palloc_commit_free_entry() Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 58/92] x86/bugs: Make sure MSR_SPEC_CTRL is updated properly upon resume from S3 Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 59/92] pinctrl: intel: Save and restore pins in "direct IRQ" mode Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 60/92] net: stmmac: Set MACs flow control register to reflect current settings Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 61/92] mmc: mmc_test: Fix removal of debugfs file Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 62/92] mmc: core: Fix ambiguous TRIM and DISCARD arg Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 63/92] mmc: sdhci-esdhc-imx: correct CQHCI exit halt state check Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 64/92] mmc: sdhci-sprd: Fix no reset data and command after voltage switch Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 65/92] mmc: sdhci: Fix voltage switch delay Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 66/92] drm/amdgpu: temporarily disable broken Clang builds due to blown stack-frame Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 67/92] drm/i915: Never return 0 if not all requests retired Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 68/92] tracing: Free buffers when a used dynamic event is removed Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 69/92] io_uring: dont hold uring_lock when calling io_run_task_work* Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 70/92] ASoC: ops: Fix bounds check for _sx controls Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 71/92] pinctrl: single: Fix potential division by zero Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 72/92] iommu/vt-d: Fix PCI device refcount leak in has_external_pci() Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 73/92] iommu/vt-d: Fix PCI device refcount leak in dmar_dev_scope_init() Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 74/92] parisc: Increase size of gcc stack frame check Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 75/92] xtensa: increase " Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 76/92] parisc: Increase FRAME_WARN to 2048 bytes on parisc Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 77/92] Kconfig.debug: provide a little extra FRAME_WARN leeway when KASAN is enabled Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 78/92] selftests: net: add delete nexthop route warning test Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 79/92] selftests: net: fix nexthop warning cleanup double ip typo Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 80/92] ipv4: Handle attempt to delete multipath route when fib_info contains an nh reference Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 81/92] ipv4: Fix route deletion when nexthop info is not specified Greg Kroah-Hartman
2022-12-05 19:10 ` Greg Kroah-Hartman [this message]
2022-12-05 19:10 ` [PATCH 5.10 83/92] x86/tsx: Add a feature bit for TSX control MSR support Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 84/92] x86/pm: Add enumeration check before spec MSRs save/restore setup Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 85/92] i2c: npcm7xx: Fix error handling in npcm_i2c_init() Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 86/92] i2c: imx: Only DMA messages with I2C_M_DMA_SAFE flag set Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 87/92] ACPI: HMAT: remove unnecessary variable initialization Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 88/92] ACPI: HMAT: Fix initiator registration for single-initiator systems Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 89/92] Revert "clocksource/drivers/riscv: Events are stopped during CPU suspend" Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 90/92] char: tpm: Protect tpm_pm_suspend with locks Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 91/92] Input: raydium_ts_i2c - fix memory leak in raydium_i2c_send() Greg Kroah-Hartman
2022-12-05 19:10 ` [PATCH 5.10 92/92] [PATCH 5.10.y stable v2] block: unhash blkdev part inode when the part is deleted Greg Kroah-Hartman
2022-12-05 23:34 ` [PATCH 5.10 00/92] 5.10.158-rc1 review Florian Fainelli
2022-12-06 2:37 ` Shuah Khan
2022-12-06 10:24 ` Pavel Machek
2022-12-06 12:27 ` Rudi Heitbaum
2022-12-07 9:34 ` zhouzhixiu
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