linux/drivers/dma-buf/sync_debug.c
Tetsuo Handa b794918961 dma-buf/sw-sync: don't enable IRQ from sync_print_obj()
Since commit a6aa8fca4d ("dma-buf/sw-sync: Reduce irqsave/irqrestore from
known context") by error replaced spin_unlock_irqrestore() with
spin_unlock_irq() for both sync_debugfs_show() and sync_print_obj() despite
sync_print_obj() is called from sync_debugfs_show(), lockdep complains
inconsistent lock state warning.

Use plain spin_{lock,unlock}() for sync_print_obj(), for
sync_debugfs_show() is already using spin_{lock,unlock}_irq().

Reported-by: syzbot <syzbot+a225ee3df7e7f9372dbe@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=a225ee3df7e7f9372dbe
Fixes: a6aa8fca4d ("dma-buf/sw-sync: Reduce irqsave/irqrestore from known context")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/c2e46020-aaa6-4e06-bf73-f05823f913f0@I-love.SAKURA.ne.jp
Signed-off-by: Christian König <christian.koenig@amd.com>
2024-05-24 16:30:05 +02:00

191 lines
4.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Sync File validation framework and debug information
*
* Copyright (C) 2012 Google, Inc.
*/
#include <linux/debugfs.h>
#include "sync_debug.h"
static struct dentry *dbgfs;
static LIST_HEAD(sync_timeline_list_head);
static DEFINE_SPINLOCK(sync_timeline_list_lock);
static LIST_HEAD(sync_file_list_head);
static DEFINE_SPINLOCK(sync_file_list_lock);
void sync_timeline_debug_add(struct sync_timeline *obj)
{
unsigned long flags;
spin_lock_irqsave(&sync_timeline_list_lock, flags);
list_add_tail(&obj->sync_timeline_list, &sync_timeline_list_head);
spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
}
void sync_timeline_debug_remove(struct sync_timeline *obj)
{
unsigned long flags;
spin_lock_irqsave(&sync_timeline_list_lock, flags);
list_del(&obj->sync_timeline_list);
spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
}
void sync_file_debug_add(struct sync_file *sync_file)
{
unsigned long flags;
spin_lock_irqsave(&sync_file_list_lock, flags);
list_add_tail(&sync_file->sync_file_list, &sync_file_list_head);
spin_unlock_irqrestore(&sync_file_list_lock, flags);
}
void sync_file_debug_remove(struct sync_file *sync_file)
{
unsigned long flags;
spin_lock_irqsave(&sync_file_list_lock, flags);
list_del(&sync_file->sync_file_list);
spin_unlock_irqrestore(&sync_file_list_lock, flags);
}
static const char *sync_status_str(int status)
{
if (status < 0)
return "error";
if (status > 0)
return "signaled";
return "active";
}
static void sync_print_fence(struct seq_file *s,
struct dma_fence *fence, bool show)
{
struct sync_timeline *parent = dma_fence_parent(fence);
int status;
status = dma_fence_get_status_locked(fence);
seq_printf(s, " %s%sfence %s",
show ? parent->name : "",
show ? "_" : "",
sync_status_str(status));
if (test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags)) {
struct timespec64 ts64 =
ktime_to_timespec64(fence->timestamp);
seq_printf(s, "@%lld.%09ld", (s64)ts64.tv_sec, ts64.tv_nsec);
}
if (fence->ops->timeline_value_str &&
fence->ops->fence_value_str) {
char value[64];
bool success;
fence->ops->fence_value_str(fence, value, sizeof(value));
success = strlen(value);
if (success) {
seq_printf(s, ": %s", value);
fence->ops->timeline_value_str(fence, value,
sizeof(value));
if (strlen(value))
seq_printf(s, " / %s", value);
}
}
seq_putc(s, '\n');
}
static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj)
{
struct list_head *pos;
seq_printf(s, "%s: %d\n", obj->name, obj->value);
spin_lock(&obj->lock); /* Caller already disabled IRQ. */
list_for_each(pos, &obj->pt_list) {
struct sync_pt *pt = container_of(pos, struct sync_pt, link);
sync_print_fence(s, &pt->base, false);
}
spin_unlock(&obj->lock);
}
static void sync_print_sync_file(struct seq_file *s,
struct sync_file *sync_file)
{
char buf[128];
int i;
seq_printf(s, "[%p] %s: %s\n", sync_file,
sync_file_get_name(sync_file, buf, sizeof(buf)),
sync_status_str(dma_fence_get_status(sync_file->fence)));
if (dma_fence_is_array(sync_file->fence)) {
struct dma_fence_array *array = to_dma_fence_array(sync_file->fence);
for (i = 0; i < array->num_fences; ++i)
sync_print_fence(s, array->fences[i], true);
} else {
sync_print_fence(s, sync_file->fence, true);
}
}
static int sync_info_debugfs_show(struct seq_file *s, void *unused)
{
struct list_head *pos;
seq_puts(s, "objs:\n--------------\n");
spin_lock_irq(&sync_timeline_list_lock);
list_for_each(pos, &sync_timeline_list_head) {
struct sync_timeline *obj =
container_of(pos, struct sync_timeline,
sync_timeline_list);
sync_print_obj(s, obj);
seq_putc(s, '\n');
}
spin_unlock_irq(&sync_timeline_list_lock);
seq_puts(s, "fences:\n--------------\n");
spin_lock_irq(&sync_file_list_lock);
list_for_each(pos, &sync_file_list_head) {
struct sync_file *sync_file =
container_of(pos, struct sync_file, sync_file_list);
sync_print_sync_file(s, sync_file);
seq_putc(s, '\n');
}
spin_unlock_irq(&sync_file_list_lock);
return 0;
}
DEFINE_SHOW_ATTRIBUTE(sync_info_debugfs);
static __init int sync_debugfs_init(void)
{
dbgfs = debugfs_create_dir("sync", NULL);
/*
* The debugfs files won't ever get removed and thus, there is
* no need to protect it against removal races. The use of
* debugfs_create_file_unsafe() is actually safe here.
*/
debugfs_create_file_unsafe("info", 0444, dbgfs, NULL,
&sync_info_debugfs_fops);
debugfs_create_file_unsafe("sw_sync", 0644, dbgfs, NULL,
&sw_sync_debugfs_fops);
return 0;
}
late_initcall(sync_debugfs_init);