From: "Petr Tesařík" <petr@tesarici.cz>
To: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Omar Sandoval <osandov@osandov.com>, linux-debuggers@vger.kernel.org
Subject: Re: Segmentation fault with drgn + libkdumpfile
Date: Wed, 10 Jan 2024 20:58:28 +0100 [thread overview]
Message-ID: <20240110205828.0dfd3450@meshulam.tesarici.cz> (raw)
In-Reply-To: <87ply9ynp5.fsf@oracle.com>
On Wed, 10 Jan 2024 11:48:22 -0800
Stephen Brennan <stephen.s.brennan@oracle.com> wrote:
> Petr Tesařík <petr@tesarici.cz> writes:
>[...]
> > I was able to write a test case for the NULL data pointer. The bug
> > should be fixed by commit e63dab40c8cefdfc013dc57915de9852dbb283e4.
> >
> > Stephen, can you rebuild and verify with your dump file that this was
> > indeed the same bug?
>
> Hi Petr,
>
> I went ahead and pulled the latest from tip and ran my reproducer. The
> segmentation fault is indeed gone!
Great!
> I tested c10036e ("cache: Optimize data reclaim for missed entries"), to
> be exact, which contains e63dab4 as well.
I spent some time pondering whether the other call of reinit_entry() is
also affected. But it's not, so this other commit should be a no-op.
> Thank you so much for taking the time to go back & forth with me on this
> one! I suppose there's a reason that caching is one of the two hard
> problems in computer science ;)
Given that the relevant counter was decremented, it may also be seen as
an off-by-one bug. I think it's all a matter of naming things...
> I owe you a beverage of your choice next time we see each other!
Beer if in Europe, bourbon if in the US. Thanks. ;-)
Petr T
prev parent reply other threads:[~2024-01-10 19:58 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-05 18:38 Segmentation fault with drgn + libkdumpfile Stephen Brennan
2024-01-05 19:23 ` Petr Tesařík
2024-01-05 21:53 ` Stephen Brennan
2024-01-08 20:40 ` Petr Tesařík
2024-01-09 9:06 ` Petr Tesařík
2024-01-10 1:40 ` Stephen Brennan
2024-01-10 8:36 ` Petr Tesařík
2024-01-10 13:49 ` Petr Tesařík
2024-01-10 18:03 ` Petr Tesařík
2024-01-10 19:48 ` Stephen Brennan
2024-01-10 19:58 ` Petr Tesařík [this message]
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