From: John Wood <john.wood@gmx.com>
To: "Valdis Klētnieks" <valdis.kletnieks@vt.edu>
Cc: John Wood <john.wood@gmx.com>, kernelnewbies@kernelnewbies.org
Subject: Re: [PATCH 0/4] Help to debug spinlocks
Date: Mon, 21 Dec 2020 19:02:02 +0100 [thread overview]
Message-ID: <20201221180202.GA3124@ubuntu> (raw)
In-Reply-To: <7064.1608494812@turing-police>
On Sun, Dec 20, 2020 at 03:06:52PM -0500, Valdis Klētnieks wrote:
> On Sun, 20 Dec 2020 12:47:08 +0100, John Wood said:
>
> > disable interrupts. Then, the task_free hook was call from an IRQ context
> > and tried to acquire the same lock in a write state.
>
> OK, I'll bite.
>
> Why was task_free called from an IRQ context in the first place? That sounds
> awfully fishy.....
If I understand correctly is what the call trace says:
[ 200.483698] Call Trace:
[ 200.484481] <IRQ>
[ 200.485141] do_raw_write_lock+0xae/0xb0
[ 200.486265] _raw_write_lock+0x6c/0x70
[ 200.487366] brute_task_free+0x86/0xf0
[ 200.488477] security_task_free+0x27/0x50
[ 200.489657] __put_task_struct+0x6d/0x150
[ 200.490824] delayed_put_task_struct+0x9b/0x110
[ 200.492142] rcu_core+0x412/0x6d0
[ 200.493113] ? rcu_core+0x3de/0x6d0
[ 200.493864] rcu_core_si+0xe/0x10
[ 200.494568] __do_softirq+0xcf/0x428
[ 200.495325] asm_call_irq_on_stack+0x12/0x20
[ 200.496407] </IRQ>
[ 200.496969] do_softirq_own_stack+0x61/0x70
[ 200.498030] irq_exit_rcu+0xc1/0xd0
[ 200.498913] sysvec_apic_timer_interrupt+0x52/0xb0
[ 200.500179] asm_sysvec_apic_timer_interrupt+0x12/0x20
Thanks,
John Wood
_______________________________________________
Kernelnewbies mailing list
Kernelnewbies@kernelnewbies.org
https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
prev parent reply other threads:[~2020-12-21 18:02 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-19 11:46 [PATCH 0/4] Help to debug spinlocks John Wood
2020-12-19 11:46 ` [PATCH 1/4] security: Add LSM hook at the point where a task gets a fatal signal John Wood
2020-12-19 11:46 ` [PATCH 2/4] security/brute: Define a LSM and manage statistical data John Wood
2020-12-19 11:46 ` [PATCH 3/4] securtiy/brute: Detect a brute force attack John Wood
2020-12-20 11:47 ` [PATCH 0/4] Help to debug spinlocks John Wood
2020-12-20 20:06 ` Valdis Klētnieks
2020-12-21 18:02 ` John Wood [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201221180202.GA3124@ubuntu \
--to=john.wood@gmx.com \
--cc=kernelnewbies@kernelnewbies.org \
--cc=valdis.kletnieks@vt.edu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.