From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1A3DDC433E2 for ; Sun, 30 Aug 2020 06:19:56 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CEE6720757 for ; Sun, 30 Aug 2020 06:19:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="H+dq0xAe" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CEE6720757 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:46018 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kCGh1-00072k-2A for qemu-devel@archiver.kernel.org; Sun, 30 Aug 2020 02:19:55 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52550) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kCGgI-0006Sa-R2 for qemu-devel@nongnu.org; Sun, 30 Aug 2020 02:19:10 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:44166 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kCGgF-0008SI-SE for qemu-devel@nongnu.org; Sun, 30 Aug 2020 02:19:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1598768346; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qdueEY1/oWbqO+TNfreaWrPud9o32Z+0RhfvHMpp+90=; b=H+dq0xAe0eZfyZq2nBZebEXsaBVQfNhNO/TLVUtwEjagENJo/A5fqdbqFLuamOuDAG+7iq XcNls5EPosaqCMaUqcrIih3P+FYKDiPS8dI35jRvbMK1ngc9xi8ODoEep6Zgkz6ptCghQh 9+eEcg1YV0nSjyXVfGEpsvIp6RCr2ig= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-330-B7dsRhxHOIq7hUSUgZnB2A-1; Sun, 30 Aug 2020 02:18:46 -0400 X-MC-Unique: B7dsRhxHOIq7hUSUgZnB2A-1 Received: by mail-wr1-f71.google.com with SMTP id i10so1711932wrq.5 for ; Sat, 29 Aug 2020 23:18:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:date:to:cc:subject:message-id :references:mime-version:content-disposition :content-transfer-encoding:in-reply-to; bh=V2nCr2RPn1NrqT0tvAO1gfWK3iizlxVGfbl5BGyE7jU=; b=Czqft7qYHkXzbBhpPduHlP5bHdLLIs4PXa7Bi9JQSLbS0R8flGBXHmkwr88zrqGEOF SF3LTRoYYIWrCgkQO7bmeBqv7gQLbjz02vaxmF1Rkedu/6UfDGXlew7M14CXXyLmKlBN 3LpUBVatUT4oyLy2WahS66OaS0ZxlJcOPKE1YokOSc1qqMjnimTRer81NWWi6P/aZlOI 8W3iZtsazSQ4X/bRVAWA6wcZzUpsQgoJmHTlU76y8PKXQR0H6BHSbLtFSOTJj1hQvYpB lP06+FOoN+FRwHxi0shKz1yi+d0hzy+DbDgnDnTeNXXrmYQ4k+xn9O7T/+wmAy9WAVUH 35fQ== X-Gm-Message-State: AOAM532Gy22cIGxG2I0NXV65mVQQftynTGUvrn8VECBcdexhYMZehT00 P14kA/1eCFRfYM/x+N+2TnPjChunChVRkx/h6W5Z7SHIDc+mV7HPw3dQO4UtlbVEDYAWJ6AUq+u WPgII3tVkBTIyNng= X-Received: by 2002:adf:ebcf:: with SMTP id v15mr6592364wrn.372.1598768325149; Sat, 29 Aug 2020 23:18:45 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyMdNUWHYDZ+ZN1B+yAZiYvgu/Qp49U3uXeyQ4EQlJCL6Y2267ynJAyLbzzzcVVUqLu0CZzUA== X-Received: by 2002:adf:ebcf:: with SMTP id v15mr6592335wrn.372.1598768324811; Sat, 29 Aug 2020 23:18:44 -0700 (PDT) Received: from redhat.com (bzq-109-64-136-54.red.bezeqint.net. [109.64.136.54]) by smtp.gmail.com with ESMTPSA id n8sm6215160wra.32.2020.08.29.23.18.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 29 Aug 2020 23:18:43 -0700 (PDT) From: mst@redhat.com X-Google-Original-From: "Michael S. Tsirkin" , Nathan Chancellor Date: Sun, 30 Aug 2020 02:18:39 -0400 To: Bug 1892540 <1892540@bugs.launchpad.net>, "Michael S. Tsirkin" , Palmer Dabbelt , Alistair Francis , Sagar Karandikar , Bastian Koppelmann Subject: Re: [Bug 1892540] [RFC PATCH v2] hw/display/tcx: Allow 64-bit accesses to framebuffer stippler and blitter Message-ID: <20200830021257-mutt-send-email-mst@kernel.org> References: <159803735569.2614.10182276398047269277.malonedeb@chaenomeles.canonical.com> <20200822142127.1316231-1-f4bug@amsat.org> MIME-Version: 1.0 In-Reply-To: <20200822142127.1316231-1-f4bug@amsat.org> Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mst@redhat.com X-Mimecast-Spam-Score: 0.002 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Content-Disposition: inline Received-SPF: pass client-ip=205.139.110.61; envelope-from=mst@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/30 02:19:06 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.959, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Richard Henderson , qemu-riscv@nongnu.org, qemu-devel@nongnu.org, qemu-stable@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Sat, Aug 22, 2020 at 02:21:27PM -0000, Philippe Mathieu-Daudé wrote: > The S24/TCX datasheet is listed as "Unable to locate" on [1]. > > However the NetBSD revision 1.32 of the driver introduced > 64-bit accesses to the stippler and blitter [2]. It is safe > to assume these memory regions are 64-bit accessible. > QEMU implementation is 32-bit, so fill the 'impl' fields. > > [1] http://web.archive.org/web/20111209011516/http://wikis.sun.com/display/FOSSdocs/Home > [2] http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/dev/sbus/tcx.c.diff?r1=1.31&r2=1.32 > > Reported-by: Andreas Gustafsson > Buglink: https://bugs.launchpad.net/bugs/1892540 > Fixes: 55d7bfe2293 ("tcx: Implement hardware acceleration") > Signed-off-by: Philippe Mathieu-Daudé Philippe, did you submit the patch on the mailing list normally too? I don't seem to see it there. the patch seems to work for me: Tested-by: Michael S. Tsirkin CC Nathan who reported a similar failure. Nathan, does the patch below fix the issue for you? > --- > Since v1: > - added missing uncommitted staged changes... (tcx_blit_ops) > --- hw/display/tcx.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/hw/display/tcx.c b/hw/display/tcx.c index 1fb45b1aab8..96c6898b149 100644 --- a/hw/display/tcx.c +++ b/hw/display/tcx.c @@ -548,20 +548,28 @@ static const MemoryRegionOps tcx_stip_ops = { .read = tcx_stip_readl, .write = tcx_stip_writel, .endianness = DEVICE_NATIVE_ENDIAN, - .valid = { + .impl = { .min_access_size = 4, .max_access_size = 4, }, + .valid = { + .min_access_size = 4, + .max_access_size = 8, + }, }; static const MemoryRegionOps tcx_rstip_ops = { .read = tcx_stip_readl, .write = tcx_rstip_writel, .endianness = DEVICE_NATIVE_ENDIAN, - .valid = { + .impl = { .min_access_size = 4, .max_access_size = 4, }, + .valid = { + .min_access_size = 4, + .max_access_size = 8, + }, }; static uint64_t tcx_blit_readl(void *opaque, hwaddr addr, @@ -650,10 +658,14 @@ static const MemoryRegionOps tcx_rblit_ops = { .read = tcx_blit_readl, .write = tcx_rblit_writel, .endianness = DEVICE_NATIVE_ENDIAN, - .valid = { + .impl = { .min_access_size = 4, .max_access_size = 4, }, + .valid = { + .min_access_size = 4, + .max_access_size = 8, + }, }; static void tcx_invalidate_cursor_position(TCXState *s) ----------------------------------------------------------- I think you shouldn't specify .min_access_size in impl, since that also allows 1 and 2 byte accesses from guest. > -- > 2.26.2 > > -- > You received this bug notification because you are subscribed to the bug > report. > https://bugs.launchpad.net/bugs/1892540 > > Title: > qemu can no longer boot NetBSD/sparc > > Status in QEMU: > New > > Bug description: > Booting NetBSD/sparc in qemu no longer works. It broke between qemu > version 5.0.0 and 5.1.0, and a bisection identified the following as > the offending commit: > > [5d971f9e672507210e77d020d89e0e89165c8fc9] memory: Revert "memory: > accept mismatching sizes in memory_region_access_valid" > > It's still broken as of 7fd51e68c34fcefdb4d6fd646ed3346f780f89f4. > > To reproduce, run > > wget http://ftp.netbsd.org/pub/NetBSD/NetBSD-9.0/images/NetBSD-9.0-sparc.iso > qemu-system-sparc -nographic -cdrom NetBSD-9.0-sparc.iso -boot d > > The expected behavior is that the guest boots to the prompt > > Installation medium to load the additional utilities from: > > The observed behavior is a panic: > > [ 1.0000050] system[0]: trap 0x29: pc=0xf0046b14 sfsr=0xb6 sfva=0x54000000 > [ 1.0000050] cpu0: data fault: pc=0xf0046b14 addr=0x54000000 sfsr=0xb6 > [ 1.0000050] panic: kernel fault > [ 1.0000050] halted > > To manage notifications about this bug go to: > https://bugs.launchpad.net/qemu/+bug/1892540/+subscriptions From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5655DC433E2 for ; Sun, 30 Aug 2020 06:26:23 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 29CE02087D for ; Sun, 30 Aug 2020 06:26:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 29CE02087D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bugs.launchpad.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:50688 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kCGnG-0000wl-B5 for qemu-devel@archiver.kernel.org; Sun, 30 Aug 2020 02:26:22 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53146) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kCGma-0000S6-Gi for qemu-devel@nongnu.org; Sun, 30 Aug 2020 02:25:40 -0400 Received: from indium.canonical.com ([91.189.90.7]:34732) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1kCGmY-0000pR-2p for qemu-devel@nongnu.org; Sun, 30 Aug 2020 02:25:40 -0400 Received: from loganberry.canonical.com ([91.189.90.37]) by indium.canonical.com with esmtp (Exim 4.86_2 #2 (Debian)) id 1kCGmW-0004B8-8H for ; Sun, 30 Aug 2020 06:25:36 +0000 Received: from loganberry.canonical.com (localhost [127.0.0.1]) by loganberry.canonical.com (Postfix) with ESMTP id 38A732E802A for ; Sun, 30 Aug 2020 06:25:36 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Date: Sun, 30 Aug 2020 06:18:39 -0000 From: mst <1892540@bugs.launchpad.net> To: qemu-devel@nongnu.org X-Launchpad-Notification-Type: bug X-Launchpad-Bug: product=qemu; status=New; importance=Undecided; assignee=None; X-Launchpad-Bug-Tags: sparc testcase X-Launchpad-Bug-Information-Type: Public X-Launchpad-Bug-Private: no X-Launchpad-Bug-Security-Vulnerability: no X-Launchpad-Bug-Commenters: gson laurent-vivier mst-0 philmd X-Launchpad-Bug-Reporter: Andreas Gustafsson (gson) X-Launchpad-Bug-Modifier: mst (mst-0) References: <159803735569.2614.10182276398047269277.malonedeb@chaenomeles.canonical.com> <20200822142127.1316231-1-f4bug@amsat.org> Message-ID: <20200830021257-mutt-send-email-mst@kernel.org> Subject: Re: [Bug 1892540] [RFC PATCH v2] hw/display/tcx: Allow 64-bit accesses to framebuffer stippler and blitter X-Launchpad-Message-Rationale: Subscriber (QEMU) @qemu-devel-ml X-Launchpad-Message-For: qemu-devel-ml Precedence: bulk X-Generated-By: Launchpad (canonical.com); Revision="195cbfa84cb75815472f69dd83d46f006869050b"; Instance="production" X-Launchpad-Hash: ea6cfa27aa93f7057e13772e49e7f192bfc4e003 Received-SPF: none client-ip=91.189.90.7; envelope-from=bounces@canonical.com; helo=indium.canonical.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/30 02:25:36 X-ACL-Warn: Detected OS = Linux 3.11 and newer [fuzzy] X-Spam_score_int: -65 X-Spam_score: -6.6 X-Spam_bar: ------ X-Spam_report: (-6.6 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.25, RCVD_IN_DNSWL_HI=-5, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Bug 1892540 <1892540@bugs.launchpad.net> Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Message-ID: <20200830061839.NW8QbuP-IJ93npHMZUx40X-xIzLXVHuFzIO9B8Y_gBc@z> On Sat, Aug 22, 2020 at 02:21:27PM -0000, Philippe Mathieu-Daud=C3=83=C2=A9= wrote: > The S24/TCX datasheet is listed as "Unable to locate" on [1]. > = > However the NetBSD revision 1.32 of the driver introduced > 64-bit accesses to the stippler and blitter [2]. It is safe > to assume these memory regions are 64-bit accessible. > QEMU implementation is 32-bit, so fill the 'impl' fields. > = > [1] http://web.archive.org/web/20111209011516/http://wikis.sun.com/displa= y/FOSSdocs/Home > [2] http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/dev/sbus/tcx.c.diff?r1=3D= 1.31&r2=3D1.32 > = > Reported-by: Andreas Gustafsson > Buglink: https://bugs.launchpad.net/bugs/1892540 > Fixes: 55d7bfe2293 ("tcx: Implement hardware acceleration") > Signed-off-by: Philippe Mathieu-Daud=C3=83=C2=A9 Philippe, did you submit the patch on the mailing list normally too? I don't seem to see it there. the patch seems to work for me: Tested-by: Michael S. Tsirkin CC Nathan who reported a similar failure. Nathan, does the patch below fix the issue for you? > --- > Since v1: > - added missing uncommitted staged changes... (tcx_blit_ops) > --- hw/display/tcx.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/hw/display/tcx.c b/hw/display/tcx.c index 1fb45b1aab8..96c6898b149 100644 --- a/hw/display/tcx.c +++ b/hw/display/tcx.c @@ -548,20 +548,28 @@ static const MemoryRegionOps tcx_stip_ops =3D { .read =3D tcx_stip_readl, .write =3D tcx_stip_writel, .endianness =3D DEVICE_NATIVE_ENDIAN, - .valid =3D { + .impl =3D { .min_access_size =3D 4, .max_access_size =3D 4, }, + .valid =3D { + .min_access_size =3D 4, + .max_access_size =3D 8, + }, }; = static const MemoryRegionOps tcx_rstip_ops =3D { .read =3D tcx_stip_readl, .write =3D tcx_rstip_writel, .endianness =3D DEVICE_NATIVE_ENDIAN, - .valid =3D { + .impl =3D { .min_access_size =3D 4, .max_access_size =3D 4, }, + .valid =3D { + .min_access_size =3D 4, + .max_access_size =3D 8, + }, }; = static uint64_t tcx_blit_readl(void *opaque, hwaddr addr, @@ -650,10 +658,14 @@ static const MemoryRegionOps tcx_rblit_ops =3D { .read =3D tcx_blit_readl, .write =3D tcx_rblit_writel, .endianness =3D DEVICE_NATIVE_ENDIAN, - .valid =3D { + .impl =3D { .min_access_size =3D 4, .max_access_size =3D 4, }, + .valid =3D { + .min_access_size =3D 4, + .max_access_size =3D 8, + }, }; = static void tcx_invalidate_cursor_position(TCXState *s) ----------------------------------------------------------- I think you shouldn't specify .min_access_size in impl, since that also allows 1 and 2 byte accesses from guest. > -- = > 2.26.2 > = > -- = > You received this bug notification because you are subscribed to the bug > report. > https://bugs.launchpad.net/bugs/1892540 > = > Title: > qemu can no longer boot NetBSD/sparc > = > Status in QEMU: > New > = > Bug description: > Booting NetBSD/sparc in qemu no longer works. It broke between qemu > version 5.0.0 and 5.1.0, and a bisection identified the following as > the offending commit: > = > [5d971f9e672507210e77d020d89e0e89165c8fc9] memory: Revert "memory: > accept mismatching sizes in memory_region_access_valid" > = > It's still broken as of 7fd51e68c34fcefdb4d6fd646ed3346f780f89f4. > = > To reproduce, run > = > wget http://ftp.netbsd.org/pub/NetBSD/NetBSD-9.0/images/NetBSD-9.0-sp= arc.iso > qemu-system-sparc -nographic -cdrom NetBSD-9.0-sparc.iso -boot d > = > The expected behavior is that the guest boots to the prompt > = > Installation medium to load the additional utilities from: > = > The observed behavior is a panic: > = > [ 1.0000050] system[0]: trap 0x29: pc=3D0xf0046b14 sfsr=3D0xb6 sfva= =3D0x54000000 > [ 1.0000050] cpu0: data fault: pc=3D0xf0046b14 addr=3D0x54000000 sf= sr=3D0xb6 > [ 1.0000050] panic: kernel fault > [ 1.0000050] halted > = > To manage notifications about this bug go to: > https://bugs.launchpad.net/qemu/+bug/1892540/+subscriptions -- = You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1892540 Title: qemu can no longer boot NetBSD/sparc Status in QEMU: New Bug description: Booting NetBSD/sparc in qemu no longer works. It broke between qemu version 5.0.0 and 5.1.0, and a bisection identified the following as the offending commit: [5d971f9e672507210e77d020d89e0e89165c8fc9] memory: Revert "memory: accept mismatching sizes in memory_region_access_valid" It's still broken as of 7fd51e68c34fcefdb4d6fd646ed3346f780f89f4. To reproduce, run wget http://ftp.netbsd.org/pub/NetBSD/NetBSD-9.0/images/NetBSD-9.0-spar= c.iso qemu-system-sparc -nographic -cdrom NetBSD-9.0-sparc.iso -boot d The expected behavior is that the guest boots to the prompt Installation medium to load the additional utilities from: The observed behavior is a panic: [ 1.0000050] system[0]: trap 0x29: pc=3D0xf0046b14 sfsr=3D0xb6 sfva= =3D0x54000000 [ 1.0000050] cpu0: data fault: pc=3D0xf0046b14 addr=3D0x54000000 sfsr= =3D0xb6 [ 1.0000050] panic: kernel fault [ 1.0000050] halted To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1892540/+subscriptions