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Shutemov" , Andi Kleen , tony.luck@intel.com, marcorr@google.com, sathyanarayanan.kuppuswamy@linux.intel.com Subject: Re: [PATCH Part2 v5 00/45] Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support Message-ID: References: <20210820155918.7518-1-brijesh.singh@amd.com> <061ccd49-3b9f-d603-bafd-61a067c3f6fa@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 647AA1052E51 X-Stat-Signature: sa3sef4ymh7gc9bcz7u5extayec9rpmq Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=S5RPaaB1; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=piTY591k; spf=pass (imf13.hostedemail.com: domain of jroedel@suse.de designates 195.135.220.28 as permitted sender) smtp.mailfrom=jroedel@suse.de; dmarc=pass (policy=none) header.from=suse.de X-HE-Tag: 1636993249-22713 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Nov 15, 2021 at 03:33:03PM +0000, Dr. David Alan Gilbert wrote: > How would you debug an unexpected access by the host kernel using a > guests kdump? The host needs to log the access in some way (trace-event, pr_err) with relevant information. And with the guest-side kdump you can rule out that it was a guest bug which triggered the access. And you learn what the guest was trying to do when it triggered the access. This also helps finding the issue on the host side (if it is a host-side issue). (Guest and host owner need to work together for debugging, of course). Regards, --=20 J=F6rg R=F6del jroedel@suse.de SUSE Software Solutions Germany GmbH Maxfeldstr. 5 90409 N=FCrnberg Germany =20 (HRB 36809, AG N=FCrnberg) Gesch=E4ftsf=FChrer: Ivo Totev