Re: [PATCH] x86: Do not reserve a crash kernel region if booted on Xen PV

From: Juergen Gross
Date: Wed Apr 25 2018 - 08:53:18 EST

On 25/04/18 12:08, Petr Tesarik wrote:
> Xen PV domains cannot shut down and start a crash kernel. Instead,
> the crashing kernel makes a SCHEDOP_shutdown hypercall with the
> reason code SHUTDOWN_crash, cf. xen_crash_shutdown() machine op in
> arch/x86/xen/enlighten_pv.c.
> A crash kernel reservation is merely a waste of RAM in this case. It
> may also confuse users of kexec_load(2) and/or kexec_file_load(2).
> When flags include KEXEC_ON_CRASH or KEXEC_FILE_ON_CRASH,
> respectively, these syscalls return success, which is technically
> correct, but the crash kexec image will never be actually used.
> Signed-off-by: Petr Tesarik <ptesarik@xxxxxxxx>

Reviewed-by: Juergen Gross <jgross@xxxxxxxx>