linux/drivers/usb/host/xhci-dbgtty.c

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// SPDX-License-Identifier: GPL-2.0
/**
* xhci-dbgtty.c - tty glue for xHCI debug capability
*
* Copyright (C) 2017 Intel Corporation
*
* Author: Lu Baolu <baolu.lu@linux.intel.com>
*/
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include "xhci.h"
#include "xhci-dbgcap.h"
static unsigned int
dbc_send_packet(struct dbc_port *port, char *packet, unsigned int size)
{
unsigned int len;
len = kfifo_len(&port->write_fifo);
if (len < size)
size = len;
if (size != 0)
size = kfifo_out(&port->write_fifo, packet, size);
return size;
}
static int dbc_start_tx(struct dbc_port *port)
__releases(&port->port_lock)
__acquires(&port->port_lock)
{
int len;
struct dbc_request *req;
int status = 0;
bool do_tty_wake = false;
struct list_head *pool = &port->write_pool;
while (!list_empty(pool)) {
req = list_entry(pool->next, struct dbc_request, list_pool);
len = dbc_send_packet(port, req->buf, DBC_MAX_PACKET);
if (len == 0)
break;
do_tty_wake = true;
req->length = len;
list_del(&req->list_pool);
spin_unlock(&port->port_lock);
status = dbc_ep_queue(port->out, req, GFP_ATOMIC);
spin_lock(&port->port_lock);
if (status) {
list_add(&req->list_pool, pool);
break;
}
}
if (do_tty_wake && port->port.tty)
tty_wakeup(port->port.tty);
return status;
}
static void dbc_start_rx(struct dbc_port *port)
__releases(&port->port_lock)
__acquires(&port->port_lock)
{
struct dbc_request *req;
int status;
struct list_head *pool = &port->read_pool;
while (!list_empty(pool)) {
if (!port->port.tty)
break;
req = list_entry(pool->next, struct dbc_request, list_pool);
list_del(&req->list_pool);
req->length = DBC_MAX_PACKET;
spin_unlock(&port->port_lock);
status = dbc_ep_queue(port->in, req, GFP_ATOMIC);
spin_lock(&port->port_lock);
if (status) {
list_add(&req->list_pool, pool);
break;
}
}
}
static void
dbc_read_complete(struct xhci_hcd *xhci, struct dbc_request *req)
{
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
unsigned long flags;
struct xhci_dbc *dbc = xhci->dbc;
struct dbc_port *port = &dbc->port;
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
spin_lock_irqsave(&port->port_lock, flags);
list_add_tail(&req->list_pool, &port->read_queue);
tasklet_schedule(&port->push);
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
spin_unlock_irqrestore(&port->port_lock, flags);
}
static void dbc_write_complete(struct xhci_hcd *xhci, struct dbc_request *req)
{
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
unsigned long flags;
struct xhci_dbc *dbc = xhci->dbc;
struct dbc_port *port = &dbc->port;
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
spin_lock_irqsave(&port->port_lock, flags);
list_add(&req->list_pool, &port->write_pool);
switch (req->status) {
case 0:
dbc_start_tx(port);
break;
case -ESHUTDOWN:
break;
default:
xhci_warn(xhci, "unexpected write complete status %d\n",
req->status);
break;
}
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
spin_unlock_irqrestore(&port->port_lock, flags);
}
static void xhci_dbc_free_req(struct dbc_ep *dep, struct dbc_request *req)
{
kfree(req->buf);
dbc_free_request(dep, req);
}
static int
xhci_dbc_alloc_requests(struct dbc_ep *dep, struct list_head *head,
void (*fn)(struct xhci_hcd *, struct dbc_request *))
{
int i;
struct dbc_request *req;
for (i = 0; i < DBC_QUEUE_SIZE; i++) {
req = dbc_alloc_request(dep, GFP_KERNEL);
if (!req)
break;
req->length = DBC_MAX_PACKET;
req->buf = kmalloc(req->length, GFP_KERNEL);
if (!req->buf) {
dbc_free_request(dep, req);
break;
}
req->complete = fn;
list_add_tail(&req->list_pool, head);
}
return list_empty(head) ? -ENOMEM : 0;
}
static void
xhci_dbc_free_requests(struct dbc_ep *dep, struct list_head *head)
{
struct dbc_request *req;
while (!list_empty(head)) {
req = list_entry(head->next, struct dbc_request, list_pool);
list_del(&req->list_pool);
xhci_dbc_free_req(dep, req);
}
}
static int dbc_tty_install(struct tty_driver *driver, struct tty_struct *tty)
{
struct dbc_port *port = driver->driver_state;
tty->driver_data = port;
return tty_port_install(&port->port, driver, tty);
}
static int dbc_tty_open(struct tty_struct *tty, struct file *file)
{
struct dbc_port *port = tty->driver_data;
return tty_port_open(&port->port, tty, file);
}
static void dbc_tty_close(struct tty_struct *tty, struct file *file)
{
struct dbc_port *port = tty->driver_data;
tty_port_close(&port->port, tty, file);
}
static int dbc_tty_write(struct tty_struct *tty,
const unsigned char *buf,
int count)
{
struct dbc_port *port = tty->driver_data;
unsigned long flags;
spin_lock_irqsave(&port->port_lock, flags);
if (count)
count = kfifo_in(&port->write_fifo, buf, count);
dbc_start_tx(port);
spin_unlock_irqrestore(&port->port_lock, flags);
return count;
}
static int dbc_tty_put_char(struct tty_struct *tty, unsigned char ch)
{
struct dbc_port *port = tty->driver_data;
unsigned long flags;
int status;
spin_lock_irqsave(&port->port_lock, flags);
status = kfifo_put(&port->write_fifo, ch);
spin_unlock_irqrestore(&port->port_lock, flags);
return status;
}
static void dbc_tty_flush_chars(struct tty_struct *tty)
{
struct dbc_port *port = tty->driver_data;
unsigned long flags;
spin_lock_irqsave(&port->port_lock, flags);
dbc_start_tx(port);
spin_unlock_irqrestore(&port->port_lock, flags);
}
static int dbc_tty_write_room(struct tty_struct *tty)
{
struct dbc_port *port = tty->driver_data;
unsigned long flags;
int room = 0;
spin_lock_irqsave(&port->port_lock, flags);
room = kfifo_avail(&port->write_fifo);
spin_unlock_irqrestore(&port->port_lock, flags);
return room;
}
static int dbc_tty_chars_in_buffer(struct tty_struct *tty)
{
struct dbc_port *port = tty->driver_data;
unsigned long flags;
int chars = 0;
spin_lock_irqsave(&port->port_lock, flags);
chars = kfifo_len(&port->write_fifo);
spin_unlock_irqrestore(&port->port_lock, flags);
return chars;
}
static void dbc_tty_unthrottle(struct tty_struct *tty)
{
struct dbc_port *port = tty->driver_data;
unsigned long flags;
spin_lock_irqsave(&port->port_lock, flags);
tasklet_schedule(&port->push);
spin_unlock_irqrestore(&port->port_lock, flags);
}
static const struct tty_operations dbc_tty_ops = {
.install = dbc_tty_install,
.open = dbc_tty_open,
.close = dbc_tty_close,
.write = dbc_tty_write,
.put_char = dbc_tty_put_char,
.flush_chars = dbc_tty_flush_chars,
.write_room = dbc_tty_write_room,
.chars_in_buffer = dbc_tty_chars_in_buffer,
.unthrottle = dbc_tty_unthrottle,
};
static struct tty_driver *dbc_tty_driver;
int xhci_dbc_tty_register_driver(struct xhci_hcd *xhci)
{
int status;
struct xhci_dbc *dbc = xhci->dbc;
dbc_tty_driver = tty_alloc_driver(1, TTY_DRIVER_REAL_RAW |
TTY_DRIVER_DYNAMIC_DEV);
if (IS_ERR(dbc_tty_driver)) {
status = PTR_ERR(dbc_tty_driver);
dbc_tty_driver = NULL;
return status;
}
dbc_tty_driver->driver_name = "dbc_serial";
dbc_tty_driver->name = "ttyDBC";
dbc_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
dbc_tty_driver->subtype = SERIAL_TYPE_NORMAL;
dbc_tty_driver->init_termios = tty_std_termios;
dbc_tty_driver->init_termios.c_cflag =
B9600 | CS8 | CREAD | HUPCL | CLOCAL;
dbc_tty_driver->init_termios.c_ispeed = 9600;
dbc_tty_driver->init_termios.c_ospeed = 9600;
dbc_tty_driver->driver_state = &dbc->port;
tty_set_operations(dbc_tty_driver, &dbc_tty_ops);
status = tty_register_driver(dbc_tty_driver);
if (status) {
xhci_err(xhci,
"can't register dbc tty driver, err %d\n", status);
put_tty_driver(dbc_tty_driver);
dbc_tty_driver = NULL;
}
return status;
}
void xhci_dbc_tty_unregister_driver(void)
{
xhci: Fix Kernel oops in xhci dbgtty tty_unregister_driver may be called more than 1 time in some hotplug cases,it will cause the kernel oops. This patch checked dbc_tty_driver to make sure it is unregistered only 1 time. [ 175.741404] BUG: unable to handle kernel NULL pointer dereference at 0000000000000034 [ 175.742309] IP: tty_unregister_driver+0x9/0x70 [ 175.743148] PGD 0 P4D 0 [ 175.743981] Oops: 0000 [#1] SMP PTI [ 175.753904] RIP: 0010:tty_unregister_driver+0x9/0x70 [ 175.754817] RSP: 0018:ffffa8ff831d3bb0 EFLAGS: 00010246 [ 175.755753] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 175.756685] RDX: ffff92089c616000 RSI: ffffe64fe1b26080 RDI: 0000000000000000 [ 175.757608] RBP: ffff92086c988230 R08: 000000006c982701 R09: 00000001801e0016 [ 175.758533] R10: ffffa8ff831d3b48 R11: ffff92086c982100 R12: ffff92086c98827c [ 175.759462] R13: ffff92086c988398 R14: 0000000000000060 R15: ffff92089c5e9b40 [ 175.760401] FS: 0000000000000000(0000) GS:ffff9208a0100000(0000) knlGS:0000000000000000 [ 175.761334] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 175.762270] CR2: 0000000000000034 CR3: 000000011800a003 CR4: 00000000003606e0 [ 175.763225] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 175.764164] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 175.765091] Call Trace: [ 175.766014] xhci_dbc_tty_unregister_driver+0x11/0x30 [ 175.766960] xhci_dbc_exit+0x2a/0x40 [ 175.767889] xhci_stop+0x57/0x1c0 [ 175.768824] usb_remove_hcd+0x100/0x250 [ 175.769708] usb_hcd_pci_remove+0x68/0x130 [ 175.770574] pci_device_remove+0x3b/0xc0 [ 175.771435] device_release_driver_internal+0x157/0x230 [ 175.772343] pci_stop_bus_device+0x74/0xa0 [ 175.773205] pci_stop_bus_device+0x2b/0xa0 [ 175.774061] pci_stop_bus_device+0x2b/0xa0 [ 175.774907] pci_stop_bus_device+0x2b/0xa0 [ 175.775741] pci_stop_bus_device+0x2b/0xa0 [ 175.776618] pci_stop_bus_device+0x2b/0xa0 [ 175.777452] pci_stop_bus_device+0x2b/0xa0 [ 175.778273] pci_stop_bus_device+0x2b/0xa0 [ 175.779092] pci_stop_bus_device+0x2b/0xa0 [ 175.779908] pci_stop_bus_device+0x2b/0xa0 [ 175.780750] pci_stop_bus_device+0x2b/0xa0 [ 175.781543] pci_stop_and_remove_bus_device+0xe/0x20 [ 175.782338] pciehp_unconfigure_device+0xb8/0x160 [ 175.783128] pciehp_disable_slot+0x4f/0xd0 [ 175.783920] pciehp_power_thread+0x82/0xa0 [ 175.784766] process_one_work+0x147/0x3c0 [ 175.785564] worker_thread+0x4a/0x440 [ 175.786376] kthread+0xf8/0x130 [ 175.787174] ? rescuer_thread+0x360/0x360 [ 175.787964] ? kthread_associate_blkcg+0x90/0x90 [ 175.788798] ret_from_fork+0x35/0x40 Cc: <stable@vger.kernel.org> # 4.16 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com> Tested-by: Christian Kellner <christian@kellner.me> Reviewed-by: Christian Kellner <christian@kellner.me> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13 12:55:34 +00:00
if (dbc_tty_driver) {
tty_unregister_driver(dbc_tty_driver);
put_tty_driver(dbc_tty_driver);
dbc_tty_driver = NULL;
}
}
static void dbc_rx_push(unsigned long _port)
{
struct dbc_request *req;
struct tty_struct *tty;
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
unsigned long flags;
bool do_push = false;
bool disconnect = false;
struct dbc_port *port = (void *)_port;
struct list_head *queue = &port->read_queue;
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
spin_lock_irqsave(&port->port_lock, flags);
tty = port->port.tty;
while (!list_empty(queue)) {
req = list_first_entry(queue, struct dbc_request, list_pool);
if (tty && tty_throttled(tty))
break;
switch (req->status) {
case 0:
break;
case -ESHUTDOWN:
disconnect = true;
break;
default:
pr_warn("ttyDBC0: unexpected RX status %d\n",
req->status);
break;
}
if (req->actual) {
char *packet = req->buf;
unsigned int n, size = req->actual;
int count;
n = port->n_read;
if (n) {
packet += n;
size -= n;
}
count = tty_insert_flip_string(&port->port, packet,
size);
if (count)
do_push = true;
if (count != size) {
port->n_read += count;
break;
}
port->n_read = 0;
}
list_move(&req->list_pool, &port->read_pool);
}
if (do_push)
tty_flip_buffer_push(&port->port);
if (!list_empty(queue) && tty) {
if (!tty_throttled(tty)) {
if (do_push)
tasklet_schedule(&port->push);
else
pr_warn("ttyDBC0: RX not scheduled?\n");
}
}
if (!disconnect)
dbc_start_rx(port);
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
spin_unlock_irqrestore(&port->port_lock, flags);
}
static int dbc_port_activate(struct tty_port *_port, struct tty_struct *tty)
{
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
unsigned long flags;
struct dbc_port *port = container_of(_port, struct dbc_port, port);
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
spin_lock_irqsave(&port->port_lock, flags);
dbc_start_rx(port);
usb: xhci: dbc: Fix lockdep warning The xHCI DbC implementation might enter a deadlock situation because there is no sufficient protection against the shared data between process and softirq contexts. This can lead to the following lockdep warnings. This patch changes to use spin_{,un}lock_irq{save,restore} to avoid potential deadlock. [ 528.248084] ================================ [ 528.252914] WARNING: inconsistent lock state [ 528.257756] 4.15.0-rc1+ #1630 Not tainted [ 528.262305] -------------------------------- [ 528.267145] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 528.273953] ksoftirqd/1/17 [HC0[0]:SC1[1]:HE0:SE0] takes: [ 528.280075] (&(&port->port_lock)->rlock){+.?.}, at: [<ffffffff815396a8>] dbc_rx_push+0x38/0x1c0 [ 528.290043] {SOFTIRQ-ON-W} state was registered at: [ 528.295570] _raw_spin_lock+0x2f/0x40 [ 528.299818] dbc_write_complete+0x27/0xa0 [ 528.304458] xhci_dbc_giveback+0xd1/0x200 [ 528.309098] xhci_dbc_flush_endpoint_requests+0x50/0x70 [ 528.315116] xhci_dbc_handle_events+0x696/0x7b0 [ 528.320349] process_one_work+0x1ee/0x6e0 [ 528.324988] worker_thread+0x4a/0x430 [ 528.329236] kthread+0x13e/0x170 [ 528.332992] ret_from_fork+0x24/0x30 [ 528.337141] irq event stamp: 2861 [ 528.340897] hardirqs last enabled at (2860): [<ffffffff810674ea>] tasklet_action+0x6a/0x250 [ 528.350460] hardirqs last disabled at (2861): [<ffffffff817dc1ef>] _raw_spin_lock_irq+0xf/0x40 [ 528.360219] softirqs last enabled at (2852): [<ffffffff817e0e8c>] __do_softirq+0x3dc/0x4f9 [ 528.369683] softirqs last disabled at (2857): [<ffffffff8106805b>] run_ksoftirqd+0x1b/0x60 [ 528.379048] [ 528.379048] other info that might help us debug this: [ 528.386443] Possible unsafe locking scenario: [ 528.386443] [ 528.393150] CPU0 [ 528.395917] ---- [ 528.398687] lock(&(&port->port_lock)->rlock); [ 528.403821] <Interrupt> [ 528.406786] lock(&(&port->port_lock)->rlock); [ 528.412116] [ 528.412116] *** DEADLOCK *** [ 528.412116] [ 528.418825] no locks held by ksoftirqd/1/17. [ 528.423662] [ 528.423662] stack backtrace: [ 528.428598] CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.15.0-rc1+ #1630 [ 528.436387] Call Trace: [ 528.439158] dump_stack+0x5e/0x8e [ 528.442914] print_usage_bug+0x1fc/0x220 [ 528.447357] mark_lock+0x4db/0x5a0 [ 528.451210] __lock_acquire+0x726/0x1130 [ 528.455655] ? __lock_acquire+0x557/0x1130 [ 528.460296] lock_acquire+0xa2/0x200 [ 528.464347] ? dbc_rx_push+0x38/0x1c0 [ 528.468496] _raw_spin_lock_irq+0x35/0x40 [ 528.473038] ? dbc_rx_push+0x38/0x1c0 [ 528.477186] dbc_rx_push+0x38/0x1c0 [ 528.481139] tasklet_action+0x1d2/0x250 [ 528.485483] __do_softirq+0x1dc/0x4f9 [ 528.489630] run_ksoftirqd+0x1b/0x60 [ 528.493682] smpboot_thread_fn+0x179/0x270 [ 528.498324] kthread+0x13e/0x170 [ 528.501981] ? sort_range+0x20/0x20 [ 528.505933] ? kthread_delayed_work_timer_fn+0x80/0x80 [ 528.511755] ret_from_fork+0x24/0x30 Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 15:17:15 +00:00
spin_unlock_irqrestore(&port->port_lock, flags);
return 0;
}
static const struct tty_port_operations dbc_port_ops = {
.activate = dbc_port_activate,
};
static void
xhci_dbc_tty_init_port(struct xhci_hcd *xhci, struct dbc_port *port)
{
tty_port_init(&port->port);
spin_lock_init(&port->port_lock);
tasklet_init(&port->push, dbc_rx_push, (unsigned long)port);
INIT_LIST_HEAD(&port->read_pool);
INIT_LIST_HEAD(&port->read_queue);
INIT_LIST_HEAD(&port->write_pool);
port->in = get_in_ep(xhci);
port->out = get_out_ep(xhci);
port->port.ops = &dbc_port_ops;
port->n_read = 0;
}
static void
xhci_dbc_tty_exit_port(struct dbc_port *port)
{
tasklet_kill(&port->push);
tty_port_destroy(&port->port);
}
int xhci_dbc_tty_register_device(struct xhci_hcd *xhci)
{
int ret;
struct device *tty_dev;
struct xhci_dbc *dbc = xhci->dbc;
struct dbc_port *port = &dbc->port;
xhci_dbc_tty_init_port(xhci, port);
tty_dev = tty_port_register_device(&port->port,
dbc_tty_driver, 0, NULL);
if (IS_ERR(tty_dev)) {
ret = PTR_ERR(tty_dev);
goto register_fail;
}
ret = kfifo_alloc(&port->write_fifo, DBC_WRITE_BUF_SIZE, GFP_KERNEL);
if (ret)
goto buf_alloc_fail;
ret = xhci_dbc_alloc_requests(port->in, &port->read_pool,
dbc_read_complete);
if (ret)
goto request_fail;
ret = xhci_dbc_alloc_requests(port->out, &port->write_pool,
dbc_write_complete);
if (ret)
goto request_fail;
port->registered = true;
return 0;
request_fail:
xhci_dbc_free_requests(port->in, &port->read_pool);
xhci_dbc_free_requests(port->out, &port->write_pool);
kfifo_free(&port->write_fifo);
buf_alloc_fail:
tty_unregister_device(dbc_tty_driver, 0);
register_fail:
xhci_dbc_tty_exit_port(port);
xhci_err(xhci, "can't register tty port, err %d\n", ret);
return ret;
}
void xhci_dbc_tty_unregister_device(struct xhci_hcd *xhci)
{
struct xhci_dbc *dbc = xhci->dbc;
struct dbc_port *port = &dbc->port;
tty_unregister_device(dbc_tty_driver, 0);
xhci_dbc_tty_exit_port(port);
port->registered = false;
kfifo_free(&port->write_fifo);
xhci_dbc_free_requests(get_out_ep(xhci), &port->read_pool);
xhci_dbc_free_requests(get_out_ep(xhci), &port->read_queue);
xhci_dbc_free_requests(get_in_ep(xhci), &port->write_pool);
}