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dmarc=pass (p=none dis=none) header.from=sipsolutions.net Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=sipsolutions.net header.i=@sipsolutions.net header.a=rsa-sha256 header.s=mail header.b=jcqfe0s2; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sipsolutions.net (client-ip=2a01:4f8:242:246e::2; helo=sipsolutions.net; envelope-from=johannes@sipsolutions.net; receiver=lists.ozlabs.org) Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:242:246e::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4fMgGp51vqz2xKh for ; Fri, 27 Feb 2026 18:40:34 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=MIME-Version:Content-Transfer-Encoding: Content-Type:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; 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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 X-malware-bazaar: not-scanned On Thu, 2026-02-26 at 22:45 +0100, Richard Weinberger wrote: > ----- Urspr=C3=BCngliche Mail ----- > > Von: "hch" > > XOR_SELECT_TEMPLATE is only ever called with a NULL argument, so all th= e > > ifdef'ery doesn't do anything. With our without this, the time travel > > mode should work fine on CPUs that support AVX2, as the AVX2 > > implementation is forced in this case, and won't work otherwise. >=20 > IIRC Johannes added XOR_SELECT_TEMPLATE() here to skip > the template selection logic because it didn't work with time travel mode= . >=20 > Johannes, can you please test whether this change does not break > time travel mode? It does work, even if it reports nonsense (as you'd expect): xor: measuring software checksum speed prefetch64-sse : 12816000 MB/sec sse : 12816000 MB/sec xor: using function: prefetch64-sse (12816000 MB/sec) I think it works now because the loop is using ktime and is bounded by REPS, since commit c055e3eae0f1 ("crypto: xor - use ktime for template benchmarking"). The RAID speed select still hangs, but we've gotten that removed via Kconfig, so that's already handled. Perhaps raid6_choose_gen() should use a similar algorithm? But for UML it doesn't really matter since CONFIG_RAID6_PQ_BENCHMARK exists. As far as AVX2 is concerned, yeah, I guess that was a bug, but evidently nobody (who configured time-travel) ever cared - what _did_ matter though in practice is that the boot not get stuck entirely... Two completely separate issues. johannes