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Peter Anvin" , Juergen Gross , Alexey Dobriyan , Boris Ostrovsky , kernel-dev@igalia.com, linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, kernel test robot Subject: Re: [PATCH v4 0/4] x86/pvh: fix unbootable VMs again (PVH + KASAN) In-Reply-To: <20260530220453.GAahtfBVv2hydidbnW@fat_crate.local> References: <20260526-pvh-kasan-inline-v4-0-a310e6a25ecd@igalia.com> <20260527204736.GBahdYaKk6kAkIUYE3@fat_crate.local> <274609541a0c7c6b49b386001967dd2b@igalia.com> <20260530220453.GAahtfBVv2hydidbnW@fat_crate.local> Message-ID: <7f1af7169b4f8c90abae28cebd3e377f@igalia.com> X-Sender: mfo@igalia.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Spam-Report: NO, Score=-4.8, Tests=ALL_TRUSTED=-3,AWL=-2.550,BAYES_50=0.8 X-Spam-Score: -47 X-Spam-Bar: ---- On 2026-05-30 19:04, Borislav Petkov wrote: > On Sat, May 30, 2026 at 03:25:25PM -0300, Mauricio Faria de Oliveira wrote: >> In this instance, the use case is to speed up the dev-test cycle when >> debugging on VMs: PVH allows booting directly from vmlinux, avoiding the >> need to build/compress and decompress bzImage, while KASAN helps detect >> issues early. > > Makes sense in itself. And you can't do your use case with KVM? It has to be > Xen? It uses KVM, actually. IIUIC, the PVH entry point was originally developed for Xen, but later QEMU support was added for KVM as well. (found this blog post [1] with a nice summary and links about it.) >> Briefly, this is a side effect of reusing code from 'boot/string.c' >> through , which introduces additional complications; >> please see patch 1 for details. >> >> These complications could be avoided by not reusing that code and >> instead adding slightly duplicated code [1] directly to , >> if that is preferred. > > I'll take a look. Ok, thanks! > > Thx. -- Mauricio