shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-09 04:10:18 +09:00
Code Issues Packages Projects Releases Wiki Activity

UPSTREAM: um: line: Don't free winch (with IRQ) under spinlock

Browse Source 
Lockdep correctly complains that one shouldn't call um_free_irq()
with free_irq() inside under a spinlock since that will attempt
to acquire a mutex.

Rearrange the code to keep the list manipulations under the lock
while moving the actual freeing outside of it, to avoid this.

In particular, this removes the lockdep complaint at shutdown that
I was seeing with lockdep enabled.

Bug: 176213565
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-By: anton.ivanov@cambridgegreys.com
Signed-off-by: Richard Weinberger <richard@nod.at>
(cherry picked from commit f4ab7818ef)
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I05c323dd19cf55273fc14adc36841e41207caeb3
This commit is contained in:
Johannes Berg
2020-12-04 16:22:44 +01:00
committed by Greg Kroah-Hartman
parent db699bd0dd
commit aa8dbad09b
1 changed files with 8 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
arch/um/drivers/line.c
View File

@@ -608,7 +608,6 @@ static void free_winch(struct winch *winch)
winch->fd = -1;
if (fd != -1)
os_close_file(fd);
list_del(&winch->list);
__free_winch(&winch->work);
}
@@ -709,6 +708,8 @@ static void unregister_winch(struct tty_struct *tty)
winch = list_entry(ele, struct winch, list);
wtty = tty_port_tty_get(winch->port);
if (wtty == tty) {
list_del(&winch->list);
spin_unlock(&winch_handler_lock);
free_winch(winch);
break;
}
@@ -719,14 +720,17 @@ static void unregister_winch(struct tty_struct *tty)
static void winch_cleanup(void)
{
struct list_head *ele, *next;
struct winch *winch;
spin_lock(&winch_handler_lock);
while ((winch = list_first_entry_or_null(&winch_handlers,
struct winch, list))) {
list_del(&winch->list);
spin_unlock(&winch_handler_lock);
list_for_each_safe(ele, next, &winch_handlers) {
winch = list_entry(ele, struct winch, list);
free_winch(winch);
spin_lock(&winch_handler_lock);
}
spin_unlock(&winch_handler_lock);