SOURCES/slof-virtio-serial-Do-not-close-stdout-on-quiesce.patch

@@ -0,0 +1,87 @@
+From 27f045e2d52ee49ddbb375b5593d4fc387aad4b0 Mon Sep 17 00:00:00 2001
+From: Jordan Niethe <jniethe5@gmail.com>
+Date: Tue, 29 Aug 2023 10:12:01 +1000
+Subject: [PATCH 2/2] virtio-serial: Do not close stdout on quiesce
+
+RH-Author: Thomas Huth <thuth@redhat.com>
+RH-MergeRequest: 1: Fix SLOF crash when only using virtio console (without spapr-vty)
+RH-Jira: RHEL-3709
+RH-Acked-by: David Gibson (Red Hat) <dgibson@redhat.com>
+RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
+RH-Commit: [2/2] cbde239703a11aa2676a12b8415281d37cba54a5
+
+Commit 76fee95 ("slof: Only close stdout for virtio-serial devices")
+says that commit cf28264 ("virtio-serial: Rework shutdown sequence")
+fixed a hang. The problem was believed to be that it was necessary to
+close stdout to shutdown the underlying virtio device.
+
+Commit cf28264 ("virtio-serial: Rework shutdown sequence") closed stdout
+on quiesce. This meant when prom_init() called write on stdout after
+quiesce, there is a use after free so this is unreliable, and can also
+hang (especially after reboots).
+
+Quiescing is intended to put hardware into a safe state for the client
+to take over. It is incorrect for SLOF to close ihandles that the client
+could still be using, even after a quiesce.
+
+Rather than closing the stdout device, all that needs to happen is to
+ensure virtio-serial-shutdown gets called. On quiesce, close the virtio
+device, but leave the stdout device itself open.
+
+Commit 8174acd ("virtio-serial: Close device completely") handles reads
+and writes as no-ops if the underlying virtio device is closed so there
+is no problem with the client calling "write" on stdout after this, but
+no output will be displayed.
+
+Fixes: cf28264 ("virtio-serial: Rework shutdown sequence")
+Debugged-by: Kautuk Consul <kconsul@linux.vnet.ibm.com>
+Co-developed-by: Kautuk Consul <kconsul@linux.vnet.ibm.com>
+Signed-off-by: Kautuk Consul <kconsul@linux.vnet.ibm.com>
+Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
+Reviewed-by: Thomas Huth <thuth@redhat.com>
+Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
+(cherry picked from commit dd4d4ea0add97df078d571b48192adaf7c4b0d87)
+Jira: https://issues.redhat.com/browse/RHEL-3709
+Signed-off-by: Thomas Huth <thuth@redhat.com>
+---
+ board-qemu/slof/virtio-serial.fs | 12 +++++-------
+ 1 file changed, 5 insertions(+), 7 deletions(-)
+
+diff --git a/board-qemu/slof/virtio-serial.fs b/board-qemu/slof/virtio-serial.fs
+index 41e2e04..de42cc7 100644
+--- a/board-qemu/slof/virtio-serial.fs
++++ b/board-qemu/slof/virtio-serial.fs
+@@ -33,16 +33,14 @@ virtio-setup-vd VALUE virtiodev
+ : virtio-serial-term-key?  virtiodev virtio-serial-haschar ;
+ : virtio-serial-term-key   BEGIN virtio-serial-term-key? UNTIL virtiodev virtio-serial-getchar ;
+ 
+-: virtio-serial-close-stdout s" stdout" get-chosen IF decode-int nip nip close-dev THEN ;
+-
+ \ Basic device initialization - which has only to be done once
+ : init  ( -- )
+ virtiodev virtio-serial-init drop
+     TRUE to initialized?
+-    \ Linux closes stdin at some point in prom_init(). This internally triggers a
+-    \ quiesce in SLOF. We must ensure stdout gets closed as well otherwise the
+-    \ device cannot be reset properly and the boot will hang.
+-    ['] virtio-serial-close-stdout add-quiesce-xt
++    \ virtiodev must be shutdown at quiesce so the device is reset properly.
++    \ The read and write methods can be called after quiesce so must handle
++    \ virtiodev being closed.
++    ['] shutdown add-quiesce-xt
+ ;
+ 
+ 0 VALUE open-count
+@@ -62,8 +60,8 @@ virtiodev virtio-serial-init drop
+     open-count 0> IF
+         open-count 1 - dup to open-count
+         0= IF shutdown THEN
++        close
+     THEN
+-    close
+ ;
+ 
+ : write ( addr len -- actual )
+-- 
+2.41.0
+

SOURCES/slof-virtio-serial-Make-read-and-write-methods-report-fai.patch

@@ -0,0 +1,58 @@
+From 67cbc16b3e6d34cf3932f88fd32323878026d6a0 Mon Sep 17 00:00:00 2001
+From: Kautuk Consul <kconsul@linux.vnet.ibm.com>
+Date: Tue, 29 Aug 2023 10:12:00 +1000
+Subject: [PATCH 1/2] virtio-serial: Make read and write methods report failure
+
+RH-Author: Thomas Huth <thuth@redhat.com>
+RH-MergeRequest: 1: Fix SLOF crash when only using virtio console (without spapr-vty)
+RH-Jira: RHEL-3709
+RH-Acked-by: David Gibson (Red Hat) <dgibson@redhat.com>
+RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
+RH-Commit: [1/2] 7aee41dceade77a47edd794cab43672ff95896d0
+
+The read and write methods return successfully even if the virtio device
+is closed (virtiodev is 0) and it is not able to send or receive any
+characters.
+
+Make the read and write methods return 0 to indicate they did not
+succeed in this case.
+
+This also fixes an invalid stack access in the read method.
+
+Fixes: 8174acd ("virtio-serial: Close device completely")
+Signed-off-by: Kautuk Consul <kconsul@linux.vnet.ibm.com>
+Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
+Reviewed-by: Thomas Huth <thuth@redhat.com>
+Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
+(cherry picked from commit 63b66a5147069bda815989732442cb07790609db)
+Jira: https://issues.redhat.com/browse/RHEL-3709
+Signed-off-by: Thomas Huth <thuth@redhat.com>
+---
+ board-qemu/slof/virtio-serial.fs | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/board-qemu/slof/virtio-serial.fs b/board-qemu/slof/virtio-serial.fs
+index 82868e2..41e2e04 100644
+--- a/board-qemu/slof/virtio-serial.fs
++++ b/board-qemu/slof/virtio-serial.fs
+@@ -67,7 +67,7 @@ virtiodev virtio-serial-init drop
+ ;
+ 
+ : write ( addr len -- actual )
+-    virtiodev 0= IF nip EXIT THEN
++    virtiodev 0= IF 2drop 0 EXIT THEN
+     tuck
+     0 ?DO
+         dup c@ virtiodev SWAP virtio-serial-putchar
+@@ -78,7 +78,7 @@ virtiodev virtio-serial-init drop
+ 
+ : read ( addr len -- actual )
+     0= IF drop 0 EXIT THEN
+-    virtiodev 0= IF nip EXIT THEN
++    virtiodev 0= IF drop 0 EXIT THEN
+     virtiodev virtio-serial-haschar 0= IF 0 swap c! -2 EXIT THEN
+     virtiodev virtio-serial-getchar swap c! 1
+ ;
+-- 
+2.41.0
+

SPECS/SLOF.spec

@@ -4,7 +4,7 @@
 
 Name:       SLOF
 Version:    %{GITDATE}
-Release:    1%{?dist}
+Release:    2%{?dist}
 Summary:    Slimline Open Firmware
 Group:      Applications/Emulators
 License:    BSD
@@ -12,6 +12,10 @@ URL:        http://www.openfirmware.info/SLOF
 
 Source0: https://github.com/aik/SLOF/archive/qemu-slof-20210217.tar.gz
 
+# For RHEL-3709 - SLOF regression prevents VM startup
+Patch1: slof-virtio-serial-Make-read-and-write-methods-report-fai.patch
+# For RHEL-3709 - SLOF regression prevents VM startup
+Patch2: slof-virtio-serial-Do-not-close-stdout-on-quiesce.patch
 
 BuildArch: noarch
 ExclusiveArch: %{power64}
@@ -56,6 +60,12 @@ install -c -m 0644 boot_rom.bin $RPM_BUILD_ROOT%{_datadir}/qemu-kvm/slof.bin
 %{_datadir}/qemu-kvm/slof.bin
 
 %changelog
+* Wed Oct 04 2023 Jon Maloy <jmaloy@redhat.com> - 20210217-2.el8
+- slof-virtio-serial-Make-read-and-write-methods-report-fai.patch [RHEL-3709]
+- slof-virtio-serial-Do-not-close-stdout-on-quiesce.patch [RHEL-3709]
+- Resolves: RHEL-3709
+  (SLOF regression prevents VM startup)
+
 * Thu Sep 2 2021 Danilo C. L. de Paula <ddepaula@redhat.com> - 20210217-1.el8
 - Resolves: bz#2000225
   (Rebase virt:rhel module:stream based on AV-8.6)