2.5.5-pre1: Deadlocks and ALSA driver problems

2.5.5-pre1: Deadlocks and ALSA driver problems

[Jos Hulzink]

Hi,

Still fighting with the debug tools (I'm new to kernel debugging), but
maybe this info is useful to others:

2.5.5-pre1 deadlocked completely about 7 times in 40 minutes. The Magic
SysRq key didn't work anymore. Don't know if it is related, but after I
recompiled the ALSA driver as modules, the system was stable for about 4
hours. (With ALSA modules loaded, playing music, and I rebooted it myself
afterwards.)

Besides: the ALSA /proc interface is terribly broken, any cat
/proc/asound/... results in a no such device error. The ALSA /dev entries
return the same errors while opening them, but the OSS emulation layer
works fine.

System Info:
PII-333 SMP on Asus P2L97-DS (Intel LX chipset), 512 MB RAM
SB Live 5.1 soundcard

The kernel is compiled with ALSA driver and Preemptive=Y

I hope to provide you better emails in the future.

Jos

Re: 2.5.5-pre1: Deadlocks and ALSA driver problems

[Jaroslav Kysela]

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On Fri, 15 Feb 2002, Jos Hulzink wrote:

> Hi,
>
> Still fighting with the debug tools (I'm new to kernel debugging), but
> maybe this info is useful to others:
>
> 2.5.5-pre1 deadlocked completely about 7 times in 40 minutes. The Magic
> SysRq key didn't work anymore. Don't know if it is related, but after I
> recompiled the ALSA driver as modules, the system was stable for about 4
> hours. (With ALSA modules loaded, playing music, and I rebooted it myself
> afterwards.)
>
> Besides: the ALSA /proc interface is terribly broken, any cat
> /proc/asound/... results in a no such device error. The ALSA /dev entries
> return the same errors while opening them, but the OSS emulation layer
> works fine.

Attached patch for linux/sound/core/info.c fixes the problem with /proc
entries.

						Jaroslav

-----
Jaroslav Kysela <perex@suse.cz>
Linux Kernel Sound Maintainer
ALSA Project  http://www.alsa-project.org
SuSE Linux    http://www.suse.com

[-- Attachment #2: Type: TEXT/plain, Size: 1644 bytes --]

Index: info.c
===================================================================
RCS file: /cvsroot/alsa/alsa-kernel/core/info.c,v
retrieving revision 1.7
retrieving revision 1.8
diff -u -r1.7 -r1.8
--- info.c	14 Feb 2002 17:40:30 -0000	1.7
+++ info.c	15 Feb 2002 12:10:26 -0000	1.8
@@ -278,7 +278,7 @@
 	int mode, err;
 
 	down(&info_mutex);
-	p = (struct proc_dir_entry *) inode->u.generic_ip;
+	p = PDE(inode);
 	entry = p == NULL ? NULL : (snd_info_entry_t *)p->data;
 	if (entry == NULL) {
 		up(&info_mutex);
@@ -541,7 +541,7 @@
 static int snd_info_card_readlink(struct dentry *dentry,
 				  char *buffer, int buflen)
 {
-        char *s = ((struct proc_dir_entry *) dentry->d_inode->u.generic_ip)->data;
+        char *s = PDE(dentry->d_inode)->data;
 #ifndef LINUX_2_2
 	return vfs_readlink(dentry, buffer, buflen, s);
 #else
@@ -562,7 +562,7 @@
 static int snd_info_card_followlink(struct dentry *dentry,
 				    struct nameidata *nd)
 {
-        char *s = ((struct proc_dir_entry *) dentry->d_inode->u.generic_ip)->data;
+        char *s = PDE(dentry->d_inode)->data;
         return vfs_follow_link(nd, s);
 }
 #else
@@ -570,7 +570,7 @@
 					       struct dentry *base,
 					       unsigned int follow)
 {
-	char *s = ((struct proc_dir_entry *) dentry->d_inode->u.generic_ip)->data;
+	char *s = PDE(dentry->d_inode)->data;
 	return lookup_dentry(s, base, follow);
 }
 #endif
@@ -845,7 +845,7 @@
 		return;
 	}
 	MOD_INC_USE_COUNT;
-	de = (struct proc_dir_entry *) inode->u.generic_ip;
+	de = PDE(inode);
 	if (de == NULL)
 		return;
 	entry = (snd_info_entry_t *) de->data;

Re: 2.5.5-pre1: Deadlocks and ALSA driver problems

[Jos Hulzink]

On Friday 15 February 2002 13:12, Jaroslav Kysela wrote:
>
> Attached patch for linux/sound/core/info.c fixes the problem with /proc
> entries.
>

Confirmed.  /proc interface seems working as expected. 

Jos