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In-Reply-To: <153693396241.22873.15797641996113409474.stgit@hbathini.in.ibm.com>
To: Hari Bathini <hbathini@linux.ibm.com>
From: Michael Ellerman <patch-notifications@ellerman.id.au>
Cc: linuxppc-dev <linuxppc-dev@ozlabs.org>, Dave Young <dyoung@redhat.com>,
 Mahesh J Salgaonkar <mahesh@linux.ibm.com>, Petr Tesarik <ptesarik@suse.cz>
Subject: Re: powerpc/fadump: re-register firmware-assisted dump if already
 registered
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Date: Thu, 20 Sep 2018 14:21:06 +1000 (AEST)
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On Fri, 2018-09-14 at 14:06:02 UTC, Hari Bathini wrote:
> Firmware-Assisted Dump (FADump) needs to be registered again after any
> memory hot add/remove operation to update the crash memory ranges. But
> currently, the kernel returns '-EEXIST' if we try to register without
> uregistering it first. This could expose the system to racing issues
> while unregistering and registering FADump from userspace during udev
> events. Spare the userspace of this and let it be taken care of in the
> kernel space for a simpler interface.
> 
> Since this change, running 'echo 1 > /sys/kernel/fadump_registered'
> would result in re-regisering (unregistering and registering) FADump,
> if it was already registered.
> 
> Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
> Acked-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/0823c68b054bca9dc321adea829af5

cheers