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From:   Ronny Meeus <ronny.meeus@gmail.com>
Date:   Thu, 9 May 2019 10:05:15 +0200
Message-ID: <CAMJ=MEdS4+5Un77MU7dPxkOjA7-yAv-1tbt0vbUaZ8n4R_rrBQ@mail.gmail.com>
Subject: fs/pstore question
To:     linux-kernel@vger.kernel.org
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Hello

I'm using the pstore feature to log kernel crashes.

What I observe is that after reboot, always 2 entries are present in the pstore:

ls -l /mnt/pstore
total 0
-r--r--r--    1 root     root         16372 Jan  1 00:00 dmesg-ramoops-0
-r--r--r--    1 root     root         16372 Jan  1 00:00 dmesg-ramoops-1

If I do not delete the entries and force a new crash, only 2 new
entries are available
after the system is online again and the older entries are overwritten.

The reason for this is that the write index is always initialized to 0
during init.
Is this intentional? I would expect that existing entries are kept
until they are explicitly
deleted or the storage is full. In the latter case the oldest entries
can be replaced.

Best regards,
Ronny