Revision 3822d0670c9d4342794d73e0d0e615322b40438e authored by Rahul Lakkireddy on 04 June 2021, 11:18:18 UTC, committed by David S. Miller on 04 June 2021, 21:45:13 UTC
When configuring TC-MQPRIO offload, only turn off netdev carrier and don't bring physical link down in hardware. Otherwise, when the physical link is brought up again after configuration, it gets re-trained and stalls ongoing traffic. Also, when firmware is no longer accessible or crashed, avoid sending FLOWC and waiting for reply that will never come. Fix following hung_task_timeout_secs trace seen in these cases. INFO: task tc:20807 blocked for more than 122 seconds. Tainted: G S 5.13.0-rc3+ #122 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:tc state:D stack:14768 pid:20807 ppid: 19366 flags:0x00000000 Call Trace: __schedule+0x27b/0x6a0 schedule+0x37/0xa0 schedule_preempt_disabled+0x5/0x10 __mutex_lock.isra.14+0x2a0/0x4a0 ? netlink_lookup+0x120/0x1a0 ? rtnl_fill_ifinfo+0x10f0/0x10f0 __netlink_dump_start+0x70/0x250 rtnetlink_rcv_msg+0x28b/0x380 ? rtnl_fill_ifinfo+0x10f0/0x10f0 ? rtnl_calcit.isra.42+0x120/0x120 netlink_rcv_skb+0x4b/0xf0 netlink_unicast+0x1a0/0x280 netlink_sendmsg+0x216/0x440 sock_sendmsg+0x56/0x60 __sys_sendto+0xe9/0x150 ? handle_mm_fault+0x6d/0x1b0 ? do_user_addr_fault+0x1c5/0x620 __x64_sys_sendto+0x1f/0x30 do_syscall_64+0x3c/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f7f73218321 RSP: 002b:00007ffd19626208 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055b7c0a8b240 RCX: 00007f7f73218321 RDX: 0000000000000028 RSI: 00007ffd19626210 RDI: 0000000000000003 RBP: 000055b7c08680ff R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000055b7c085f5f6 R13: 000055b7c085f60a R14: 00007ffd19636470 R15: 00007ffd196262a0 Fixes: b1396c2bd675 ("cxgb4: parse and configure TC-MQPRIO offload") Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1 parent 944d671
timerfd.c
// SPDX-License-Identifier: GPL-2.0
/*
* fs/timerfd.c
*
* Copyright (C) 2007 Davide Libenzi <davidel@xmailserver.org>
*
*
* Thanks to Thomas Gleixner for code reviews and useful comments.
*
*/
#include <linux/alarmtimer.h>
#include <linux/file.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/time.h>
#include <linux/hrtimer.h>
#include <linux/anon_inodes.h>
#include <linux/timerfd.h>
#include <linux/syscalls.h>
#include <linux/compat.h>
#include <linux/rcupdate.h>
#include <linux/time_namespace.h>
struct timerfd_ctx {
union {
struct hrtimer tmr;
struct alarm alarm;
} t;
ktime_t tintv;
ktime_t moffs;
wait_queue_head_t wqh;
u64 ticks;
int clockid;
short unsigned expired;
short unsigned settime_flags; /* to show in fdinfo */
struct rcu_head rcu;
struct list_head clist;
spinlock_t cancel_lock;
bool might_cancel;
};
static LIST_HEAD(cancel_list);
static DEFINE_SPINLOCK(cancel_lock);
static inline bool isalarm(struct timerfd_ctx *ctx)
{
return ctx->clockid == CLOCK_REALTIME_ALARM ||
ctx->clockid == CLOCK_BOOTTIME_ALARM;
}
/*
* This gets called when the timer event triggers. We set the "expired"
* flag, but we do not re-arm the timer (in case it's necessary,
* tintv != 0) until the timer is accessed.
*/
static void timerfd_triggered(struct timerfd_ctx *ctx)
{
unsigned long flags;
spin_lock_irqsave(&ctx->wqh.lock, flags);
ctx->expired = 1;
ctx->ticks++;
wake_up_locked_poll(&ctx->wqh, EPOLLIN);
spin_unlock_irqrestore(&ctx->wqh.lock, flags);
}
static enum hrtimer_restart timerfd_tmrproc(struct hrtimer *htmr)
{
struct timerfd_ctx *ctx = container_of(htmr, struct timerfd_ctx,
t.tmr);
timerfd_triggered(ctx);
return HRTIMER_NORESTART;
}
static enum alarmtimer_restart timerfd_alarmproc(struct alarm *alarm,
ktime_t now)
{
struct timerfd_ctx *ctx = container_of(alarm, struct timerfd_ctx,
t.alarm);
timerfd_triggered(ctx);
return ALARMTIMER_NORESTART;
}
/*
* Called when the clock was set to cancel the timers in the cancel
* list. This will wake up processes waiting on these timers. The
* wake-up requires ctx->ticks to be non zero, therefore we increment
* it before calling wake_up_locked().
*/
void timerfd_clock_was_set(void)
{
ktime_t moffs = ktime_mono_to_real(0);
struct timerfd_ctx *ctx;
unsigned long flags;
rcu_read_lock();
list_for_each_entry_rcu(ctx, &cancel_list, clist) {
if (!ctx->might_cancel)
continue;
spin_lock_irqsave(&ctx->wqh.lock, flags);
if (ctx->moffs != moffs) {
ctx->moffs = KTIME_MAX;
ctx->ticks++;
wake_up_locked_poll(&ctx->wqh, EPOLLIN);
}
spin_unlock_irqrestore(&ctx->wqh.lock, flags);
}
rcu_read_unlock();
}
static void __timerfd_remove_cancel(struct timerfd_ctx *ctx)
{
if (ctx->might_cancel) {
ctx->might_cancel = false;
spin_lock(&cancel_lock);
list_del_rcu(&ctx->clist);
spin_unlock(&cancel_lock);
}
}
static void timerfd_remove_cancel(struct timerfd_ctx *ctx)
{
spin_lock(&ctx->cancel_lock);
__timerfd_remove_cancel(ctx);
spin_unlock(&ctx->cancel_lock);
}
static bool timerfd_canceled(struct timerfd_ctx *ctx)
{
if (!ctx->might_cancel || ctx->moffs != KTIME_MAX)
return false;
ctx->moffs = ktime_mono_to_real(0);
return true;
}
static void timerfd_setup_cancel(struct timerfd_ctx *ctx, int flags)
{
spin_lock(&ctx->cancel_lock);
if ((ctx->clockid == CLOCK_REALTIME ||
ctx->clockid == CLOCK_REALTIME_ALARM) &&
(flags & TFD_TIMER_ABSTIME) && (flags & TFD_TIMER_CANCEL_ON_SET)) {
if (!ctx->might_cancel) {
ctx->might_cancel = true;
spin_lock(&cancel_lock);
list_add_rcu(&ctx->clist, &cancel_list);
spin_unlock(&cancel_lock);
}
} else {
__timerfd_remove_cancel(ctx);
}
spin_unlock(&ctx->cancel_lock);
}
static ktime_t timerfd_get_remaining(struct timerfd_ctx *ctx)
{
ktime_t remaining;
if (isalarm(ctx))
remaining = alarm_expires_remaining(&ctx->t.alarm);
else
remaining = hrtimer_expires_remaining_adjusted(&ctx->t.tmr);
return remaining < 0 ? 0: remaining;
}
static int timerfd_setup(struct timerfd_ctx *ctx, int flags,
const struct itimerspec64 *ktmr)
{
enum hrtimer_mode htmode;
ktime_t texp;
int clockid = ctx->clockid;
htmode = (flags & TFD_TIMER_ABSTIME) ?
HRTIMER_MODE_ABS: HRTIMER_MODE_REL;
texp = timespec64_to_ktime(ktmr->it_value);
ctx->expired = 0;
ctx->ticks = 0;
ctx->tintv = timespec64_to_ktime(ktmr->it_interval);
if (isalarm(ctx)) {
alarm_init(&ctx->t.alarm,
ctx->clockid == CLOCK_REALTIME_ALARM ?
ALARM_REALTIME : ALARM_BOOTTIME,
timerfd_alarmproc);
} else {
hrtimer_init(&ctx->t.tmr, clockid, htmode);
hrtimer_set_expires(&ctx->t.tmr, texp);
ctx->t.tmr.function = timerfd_tmrproc;
}
if (texp != 0) {
if (flags & TFD_TIMER_ABSTIME)
texp = timens_ktime_to_host(clockid, texp);
if (isalarm(ctx)) {
if (flags & TFD_TIMER_ABSTIME)
alarm_start(&ctx->t.alarm, texp);
else
alarm_start_relative(&ctx->t.alarm, texp);
} else {
hrtimer_start(&ctx->t.tmr, texp, htmode);
}
if (timerfd_canceled(ctx))
return -ECANCELED;
}
ctx->settime_flags = flags & TFD_SETTIME_FLAGS;
return 0;
}
static int timerfd_release(struct inode *inode, struct file *file)
{
struct timerfd_ctx *ctx = file->private_data;
timerfd_remove_cancel(ctx);
if (isalarm(ctx))
alarm_cancel(&ctx->t.alarm);
else
hrtimer_cancel(&ctx->t.tmr);
kfree_rcu(ctx, rcu);
return 0;
}
static __poll_t timerfd_poll(struct file *file, poll_table *wait)
{
struct timerfd_ctx *ctx = file->private_data;
__poll_t events = 0;
unsigned long flags;
poll_wait(file, &ctx->wqh, wait);
spin_lock_irqsave(&ctx->wqh.lock, flags);
if (ctx->ticks)
events |= EPOLLIN;
spin_unlock_irqrestore(&ctx->wqh.lock, flags);
return events;
}
static ssize_t timerfd_read(struct file *file, char __user *buf, size_t count,
loff_t *ppos)
{
struct timerfd_ctx *ctx = file->private_data;
ssize_t res;
u64 ticks = 0;
if (count < sizeof(ticks))
return -EINVAL;
spin_lock_irq(&ctx->wqh.lock);
if (file->f_flags & O_NONBLOCK)
res = -EAGAIN;
else
res = wait_event_interruptible_locked_irq(ctx->wqh, ctx->ticks);
/*
* If clock has changed, we do not care about the
* ticks and we do not rearm the timer. Userspace must
* reevaluate anyway.
*/
if (timerfd_canceled(ctx)) {
ctx->ticks = 0;
ctx->expired = 0;
res = -ECANCELED;
}
if (ctx->ticks) {
ticks = ctx->ticks;
if (ctx->expired && ctx->tintv) {
/*
* If tintv != 0, this is a periodic timer that
* needs to be re-armed. We avoid doing it in the timer
* callback to avoid DoS attacks specifying a very
* short timer period.
*/
if (isalarm(ctx)) {
ticks += alarm_forward_now(
&ctx->t.alarm, ctx->tintv) - 1;
alarm_restart(&ctx->t.alarm);
} else {
ticks += hrtimer_forward_now(&ctx->t.tmr,
ctx->tintv) - 1;
hrtimer_restart(&ctx->t.tmr);
}
}
ctx->expired = 0;
ctx->ticks = 0;
}
spin_unlock_irq(&ctx->wqh.lock);
if (ticks)
res = put_user(ticks, (u64 __user *) buf) ? -EFAULT: sizeof(ticks);
return res;
}
#ifdef CONFIG_PROC_FS
static void timerfd_show(struct seq_file *m, struct file *file)
{
struct timerfd_ctx *ctx = file->private_data;
struct timespec64 value, interval;
spin_lock_irq(&ctx->wqh.lock);
value = ktime_to_timespec64(timerfd_get_remaining(ctx));
interval = ktime_to_timespec64(ctx->tintv);
spin_unlock_irq(&ctx->wqh.lock);
seq_printf(m,
"clockid: %d\n"
"ticks: %llu\n"
"settime flags: 0%o\n"
"it_value: (%llu, %llu)\n"
"it_interval: (%llu, %llu)\n",
ctx->clockid,
(unsigned long long)ctx->ticks,
ctx->settime_flags,
(unsigned long long)value.tv_sec,
(unsigned long long)value.tv_nsec,
(unsigned long long)interval.tv_sec,
(unsigned long long)interval.tv_nsec);
}
#else
#define timerfd_show NULL
#endif
#ifdef CONFIG_CHECKPOINT_RESTORE
static long timerfd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct timerfd_ctx *ctx = file->private_data;
int ret = 0;
switch (cmd) {
case TFD_IOC_SET_TICKS: {
u64 ticks;
if (copy_from_user(&ticks, (u64 __user *)arg, sizeof(ticks)))
return -EFAULT;
if (!ticks)
return -EINVAL;
spin_lock_irq(&ctx->wqh.lock);
if (!timerfd_canceled(ctx)) {
ctx->ticks = ticks;
wake_up_locked_poll(&ctx->wqh, EPOLLIN);
} else
ret = -ECANCELED;
spin_unlock_irq(&ctx->wqh.lock);
break;
}
default:
ret = -ENOTTY;
break;
}
return ret;
}
#else
#define timerfd_ioctl NULL
#endif
static const struct file_operations timerfd_fops = {
.release = timerfd_release,
.poll = timerfd_poll,
.read = timerfd_read,
.llseek = noop_llseek,
.show_fdinfo = timerfd_show,
.unlocked_ioctl = timerfd_ioctl,
};
static int timerfd_fget(int fd, struct fd *p)
{
struct fd f = fdget(fd);
if (!f.file)
return -EBADF;
if (f.file->f_op != &timerfd_fops) {
fdput(f);
return -EINVAL;
}
*p = f;
return 0;
}
SYSCALL_DEFINE2(timerfd_create, int, clockid, int, flags)
{
int ufd;
struct timerfd_ctx *ctx;
/* Check the TFD_* constants for consistency. */
BUILD_BUG_ON(TFD_CLOEXEC != O_CLOEXEC);
BUILD_BUG_ON(TFD_NONBLOCK != O_NONBLOCK);
if ((flags & ~TFD_CREATE_FLAGS) ||
(clockid != CLOCK_MONOTONIC &&
clockid != CLOCK_REALTIME &&
clockid != CLOCK_REALTIME_ALARM &&
clockid != CLOCK_BOOTTIME &&
clockid != CLOCK_BOOTTIME_ALARM))
return -EINVAL;
if ((clockid == CLOCK_REALTIME_ALARM ||
clockid == CLOCK_BOOTTIME_ALARM) &&
!capable(CAP_WAKE_ALARM))
return -EPERM;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
init_waitqueue_head(&ctx->wqh);
spin_lock_init(&ctx->cancel_lock);
ctx->clockid = clockid;
if (isalarm(ctx))
alarm_init(&ctx->t.alarm,
ctx->clockid == CLOCK_REALTIME_ALARM ?
ALARM_REALTIME : ALARM_BOOTTIME,
timerfd_alarmproc);
else
hrtimer_init(&ctx->t.tmr, clockid, HRTIMER_MODE_ABS);
ctx->moffs = ktime_mono_to_real(0);
ufd = anon_inode_getfd("[timerfd]", &timerfd_fops, ctx,
O_RDWR | (flags & TFD_SHARED_FCNTL_FLAGS));
if (ufd < 0)
kfree(ctx);
return ufd;
}
static int do_timerfd_settime(int ufd, int flags,
const struct itimerspec64 *new,
struct itimerspec64 *old)
{
struct fd f;
struct timerfd_ctx *ctx;
int ret;
if ((flags & ~TFD_SETTIME_FLAGS) ||
!itimerspec64_valid(new))
return -EINVAL;
ret = timerfd_fget(ufd, &f);
if (ret)
return ret;
ctx = f.file->private_data;
if (isalarm(ctx) && !capable(CAP_WAKE_ALARM)) {
fdput(f);
return -EPERM;
}
timerfd_setup_cancel(ctx, flags);
/*
* We need to stop the existing timer before reprogramming
* it to the new values.
*/
for (;;) {
spin_lock_irq(&ctx->wqh.lock);
if (isalarm(ctx)) {
if (alarm_try_to_cancel(&ctx->t.alarm) >= 0)
break;
} else {
if (hrtimer_try_to_cancel(&ctx->t.tmr) >= 0)
break;
}
spin_unlock_irq(&ctx->wqh.lock);
if (isalarm(ctx))
hrtimer_cancel_wait_running(&ctx->t.alarm.timer);
else
hrtimer_cancel_wait_running(&ctx->t.tmr);
}
/*
* If the timer is expired and it's periodic, we need to advance it
* because the caller may want to know the previous expiration time.
* We do not update "ticks" and "expired" since the timer will be
* re-programmed again in the following timerfd_setup() call.
*/
if (ctx->expired && ctx->tintv) {
if (isalarm(ctx))
alarm_forward_now(&ctx->t.alarm, ctx->tintv);
else
hrtimer_forward_now(&ctx->t.tmr, ctx->tintv);
}
old->it_value = ktime_to_timespec64(timerfd_get_remaining(ctx));
old->it_interval = ktime_to_timespec64(ctx->tintv);
/*
* Re-program the timer to the new value ...
*/
ret = timerfd_setup(ctx, flags, new);
spin_unlock_irq(&ctx->wqh.lock);
fdput(f);
return ret;
}
static int do_timerfd_gettime(int ufd, struct itimerspec64 *t)
{
struct fd f;
struct timerfd_ctx *ctx;
int ret = timerfd_fget(ufd, &f);
if (ret)
return ret;
ctx = f.file->private_data;
spin_lock_irq(&ctx->wqh.lock);
if (ctx->expired && ctx->tintv) {
ctx->expired = 0;
if (isalarm(ctx)) {
ctx->ticks +=
alarm_forward_now(
&ctx->t.alarm, ctx->tintv) - 1;
alarm_restart(&ctx->t.alarm);
} else {
ctx->ticks +=
hrtimer_forward_now(&ctx->t.tmr, ctx->tintv)
- 1;
hrtimer_restart(&ctx->t.tmr);
}
}
t->it_value = ktime_to_timespec64(timerfd_get_remaining(ctx));
t->it_interval = ktime_to_timespec64(ctx->tintv);
spin_unlock_irq(&ctx->wqh.lock);
fdput(f);
return 0;
}
SYSCALL_DEFINE4(timerfd_settime, int, ufd, int, flags,
const struct __kernel_itimerspec __user *, utmr,
struct __kernel_itimerspec __user *, otmr)
{
struct itimerspec64 new, old;
int ret;
if (get_itimerspec64(&new, utmr))
return -EFAULT;
ret = do_timerfd_settime(ufd, flags, &new, &old);
if (ret)
return ret;
if (otmr && put_itimerspec64(&old, otmr))
return -EFAULT;
return ret;
}
SYSCALL_DEFINE2(timerfd_gettime, int, ufd, struct __kernel_itimerspec __user *, otmr)
{
struct itimerspec64 kotmr;
int ret = do_timerfd_gettime(ufd, &kotmr);
if (ret)
return ret;
return put_itimerspec64(&kotmr, otmr) ? -EFAULT : 0;
}
#ifdef CONFIG_COMPAT_32BIT_TIME
SYSCALL_DEFINE4(timerfd_settime32, int, ufd, int, flags,
const struct old_itimerspec32 __user *, utmr,
struct old_itimerspec32 __user *, otmr)
{
struct itimerspec64 new, old;
int ret;
if (get_old_itimerspec32(&new, utmr))
return -EFAULT;
ret = do_timerfd_settime(ufd, flags, &new, &old);
if (ret)
return ret;
if (otmr && put_old_itimerspec32(&old, otmr))
return -EFAULT;
return ret;
}
SYSCALL_DEFINE2(timerfd_gettime32, int, ufd,
struct old_itimerspec32 __user *, otmr)
{
struct itimerspec64 kotmr;
int ret = do_timerfd_gettime(ufd, &kotmr);
if (ret)
return ret;
return put_old_itimerspec32(&kotmr, otmr) ? -EFAULT : 0;
}
#endif
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