> More excitement from https://bugzilla.kernel.org/show_bug.cgi?id=20702 > > Anyone want to take a stab at it? I know I'd be appreciative. I am > running a debug kernel with everything I could find and enable I even > remotely thought might prove helpful. Nothing has jumped out yet though. A little late, but perhaps running with the patch below might help us make a bit of progress. The idea is to dump the last /proc/net file opened and closed, so we can at least have a clue as to where the crash is coming from. This should add lines like last procfs open: /proc/2443/net/arp last procfs close: /proc/2443/net/arp to the oops output, so maybe we can zero in on things after you get a crash with this applied. - R. diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index 6e8752c..c67b8d6 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -18,6 +18,7 @@ #include <asm/stacktrace.h> +void procfs_printk_last_file(void); int panic_on_unrecovered_nmi; int panic_on_io_nmi; @@ -283,6 +284,7 @@ int __kprobes __die(const char *str, struct pt_regs *regs, long err) #endif printk("\n"); sysfs_printk_last_file(); + procfs_printk_last_file(); if (notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV) == NOTIFY_STOP) return 1; diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c index 9020ac1..1801cc1 100644 --- a/fs/proc/proc_net.c +++ b/fs/proc/proc_net.c @@ -26,6 +26,14 @@ #include "internal.h" +/* used in crash dumps to help with debugging */ +static char last_procfs_open[PATH_MAX]; +static char last_procfs_close[PATH_MAX]; +void procfs_printk_last_file(void) +{ + printk(KERN_EMERG "last procfs open: %s\n", last_procfs_open); + printk(KERN_EMERG "last procfs close: %s\n", last_procfs_close); +} static struct net *get_proc_net(const struct inode *inode) { @@ -37,9 +45,14 @@ int seq_open_net(struct inode *ino, struct file *f, { struct net *net; struct seq_net_private *p; + char *n; BUG_ON(size < sizeof(*p)); + n = d_path(&f->f_path, last_procfs_open, sizeof(last_procfs_open)); + if (!IS_ERR(n)) + memmove(last_procfs_open, n, strlen(n) + 1); + net = get_proc_net(ino); if (net == NULL) return -ENXIO; @@ -83,6 +96,11 @@ EXPORT_SYMBOL_GPL(single_open_net); int seq_release_net(struct inode *ino, struct file *f) { struct seq_file *seq; + char *n; + + n = d_path(&f->f_path, last_procfs_close, sizeof(last_procfs_close)); + if (!IS_ERR(n)) + memmove(last_procfs_close, n, strlen(n) + 1); seq = f->private_data; -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
