site_archiver@lists.apple.com Delivered-To: darwin-kernel@lists.apple.com Hi Duane,
Is that are reasonable expectation? That the functions that are printing in the middle of the kernel panic are likely not the cause of the kernel panic itself?
My concern and reason for the question is what level of buffering may be involved to delay the printing of the message?
Yes, that's a reasonable expectation (different processors/cores logging). This is because FireWireKPrintf is synchronous in that it will put the log onto the wire before returning from kprintf(). Additionally, kprintf() is kernel lock synchronized, so as to order all log messages (and make them readable). So, there isn't be any sort of delay "buffering," simply that of transmission, but that should be ordered. Of course, until a processor is halted, it will diligently continue to do work, even when others are in the process of giving up. // carlos On Feb 23, 2010, at 11:57 AM, Duane Murphy wrote:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256
I'm packing a couple of questions into this message.
I'm trying to track down the cause of an elusive kernel panic. I have the target machine connected over firewire using fwkpfv. I've adjusted the debugging strings in my kext to print using kprintf.
Question 1
I'm trying to determine which functions may have triggered the kernel panic. When the kernel panic backtrace is printed to fwkpfv, there are messages interspersed with the kernel panic. My expectation is that while the back trace is being calculated, the other processor is still running. These other messages are from that processor while the kernel panic is being processed. Then the system is halted.
Is that are reasonable expectation? That the functions that are printing in the middle of the kernel panic are likely not the cause of the kernel panic itself?
My concern and reason for the question is what level of buffering may be involved to delay the printing of the message?
Question 2
I've noticed this message after of the kernel panic logged to fwkpfv:
Attempting to commit panic log to NVRAM EFI: couldn't save panic info (err = 80000009)
I've never noticed the second message before (EFI: etc). Can someone translate that into English?
Thank you for your insight,
...Duane
-----BEGIN PGP SIGNATURE----- Version: PGP Desktop 9.10.0 (Build 500) Charset: US-ASCII
wsBVAwUBS4QzeErg9acQ4r2CAQhPGwf8DXCDttP0k7qXqt1emXH3bFApNqOYF9mR mzDLsO1eci+scjzwE9Fybuv5oUoJjobaZWSFcs+tYR1nO9eYqp/l0VUc/cyigDji Sk6eZeg5xMmUTWdhkcHvSuCZVAoxEWbJhhoLLnKoOddSDt1k8f8NlyyQNa7FrKXH Em27w6Qe22Tuvo5nIw8dW/zrNu7A7tfsTQ25kVhj0kHLXCKkpieJncbAOZ6tnnzI JwsOE57oHLjAd+nr9SVANRRhrVxrddLvwXOhycfqoujmIEBEz1MKms70MO92GfrK Jkdwa6ExQHGhdMK8KrI6o2kStq+x9RBtbRs7A9PHblB/8KQwR/ZEHw== =N1iq -----END PGP SIGNATURE----- _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/carlos%40apple.com
This email sent to carlos@apple.com
_______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.a... This email sent to site_archiver@lists.apple.com