Re: [Qemu-devel] [PATCH 1/3] sysfw: remove read-only pc_sysfw_flash_vs_rom_bug_compatible
Paolo Bonzini pbonz...@redhat.com writes:
The variable is not written anymore.
This cleans up after 9e1c2ec (which accidentally left variable
pc_sysfw_flash_vs_rom_bug_compatible behind, value always zero), and
buries dead code from commit dafb82e (which looks like it got confused
by pc_sysfw_flash_vs_rom_bug_compatible). Suggest to mention that in
the commit message.
Hunk from dafb82e in question:
-/* Currently KVM cannot execute from device memory.
- Use old rom based firmware initialization for KVM. */
-/*
- * This is a Bad Idea, because it makes enabling/disabling KVM
- * guest-visible. Let's fix it for real in QEMU 1.6.
- */
-if (kvm_enabled()) {
-if (pflash_drv != NULL) {
-fprintf(stderr, qemu: pflash cannot be used with kvm enabled\n);
-exit(1);
-} else {
-sysfw_dev-rom_only = 1;
-old_pc_system_rom_init(rom_memory, sysfw_dev-isapc_ram_fw);
-return;
+if (pc_sysfw_flash_vs_rom_bug_compatible) {
+/*
+ * This is a Bad Idea, because it makes enabling/disabling KVM
+ * guest-visible. Do it only in bug-compatibility mode.
+ */
+if (kvm_enabled()) {
+if (pflash_drv != NULL) {
+fprintf(stderr, qemu: pflash cannot be used with kvm
enabled\n);
+exit(1);
+} else {
+/* In old pc_sysfw_flash_vs_rom_bug_compatible mode, we assume
+ * that KVM cannot execute from device memory. In this case, we
+ * use old rom based firmware initialization for KVM. But,
since
+ * this is different from non-kvm mode, this behavior is
+ * undesirable */
+sysfw_dev-rom_only = 1;
+}
}
+} else if (pflash_drv == NULL) {
+/* When a pflash drive is not found, use rom-mode */
+sysfw_dev-rom_only = 1;
+} else if (kvm_enabled() !kvm_readonly_mem_enabled()) {
+/* Older KVM cannot execute from device memory. So, flash memory
+ * cannot be used unless the readonly memory kvm capability is
present. */
+fprintf(stderr, qemu: pflash with kvm requires KVM readonly memory
support\n);
+exit(1);
+}
+
+/* If rom-mode is active, use the old pc system rom initialization. */
+if (sysfw_dev-rom_only) {
+old_pc_system_rom_init(rom_memory, sysfw_dev-isapc_ram_fw);
+return;
}
Signed-off-by: Paolo Bonzini pbonz...@redhat.com
---
hw/block/pc_sysfw.c | 26 +-
1 file changed, 1 insertion(+), 25 deletions(-)
diff --git a/hw/block/pc_sysfw.c b/hw/block/pc_sysfw.c
index 412d1b0..c6d4be4 100644
--- a/hw/block/pc_sysfw.c
+++ b/hw/block/pc_sysfw.c
@@ -199,12 +199,6 @@ static void old_pc_system_rom_init(MemoryRegion
*rom_memory, bool isapc_ram_fw)
bios);
}
-/*
- * Bug-compatible flash vs. ROM selection enabled?
- * A few older machines enable this.
- */
-bool pc_sysfw_flash_vs_rom_bug_compatible;
-
void pc_system_firmware_init(MemoryRegion *rom_memory)
{
DriveInfo *pflash_drv;
@@ -222,25 +216,7 @@ void pc_system_firmware_init(MemoryRegion *rom_memory)
pflash_drv = drive_get(IF_PFLASH, 0, 0);
-if (pc_sysfw_flash_vs_rom_bug_compatible) {
-/*
- * This is a Bad Idea, because it makes enabling/disabling KVM
- * guest-visible. Do it only in bug-compatibility mode.
- */
-if (kvm_enabled()) {
-if (pflash_drv != NULL) {
-fprintf(stderr, qemu: pflash cannot be used with kvm
enabled\n);
-exit(1);
-} else {
-/* In old pc_sysfw_flash_vs_rom_bug_compatible mode, we
assume
- * that KVM cannot execute from device memory. In this case,
we
- * use old rom based firmware initialization for KVM. But,
since
- * this is different from non-kvm mode, this behavior is
- * undesirable */
-sysfw_dev-rom_only = 1;
-}
-}
-} else if (pflash_drv == NULL) {
+if (pflash_drv == NULL) {
/* When a pflash drive is not found, use rom-mode */
sysfw_dev-rom_only = 1;
} else if (kvm_enabled() !kvm_readonly_mem_enabled()) {
Re: [Qemu-devel] [PATCH 1/3] sysfw: remove read-only pc_sysfw_flash_vs_rom_bug_compatible
Jordan Justen jljus...@gmail.com writes: On Mon, Jun 3, 2013 at 8:19 AM, Paolo Bonzini pbonz...@redhat.com wrote: The variable is not written anymore. Signed-off-by: Paolo Bonzini pbonz...@redhat.com --- hw/block/pc_sysfw.c | 26 +- 1 file changed, 1 insertion(+), 25 deletions(-) diff --git a/hw/block/pc_sysfw.c b/hw/block/pc_sysfw.c index 412d1b0..c6d4be4 100644 --- a/hw/block/pc_sysfw.c +++ b/hw/block/pc_sysfw.c @@ -199,12 +199,6 @@ static void old_pc_system_rom_init(MemoryRegion *rom_memory, bool isapc_ram_fw) bios); } -/* - * Bug-compatible flash vs. ROM selection enabled? - * A few older machines enable this. - */ -bool pc_sysfw_flash_vs_rom_bug_compatible; Hmm. I think we still need this to retain the 1.2-1.5 compatible behavior. But, I think I maybe my kvm readonly series didn't properly resurrect the pc_sysfw_flash_vs_rom_bug_compatible switch. It didn't (and its commit message failed to mention it tries). Anyway, Paolo successfully argued for breaking backward compatibility: http://lists.nongnu.org/archive/html/qemu-devel/2013-05/msg02074.html
Re: [Qemu-devel] [PATCH 1/3] sysfw: remove read-only pc_sysfw_flash_vs_rom_bug_compatible
Il 04/06/2013 11:14, Markus Armbruster ha scritto: The variable is not written anymore. This cleans up after 9e1c2ec (which accidentally left variable pc_sysfw_flash_vs_rom_bug_compatible behind, value always zero), and buries dead code from commit dafb82e (which looks like it got confused by pc_sysfw_flash_vs_rom_bug_compatible). Suggest to mention that in the commit message. To be honest I didn't check it that thoroughly---I was just rebasing old patches. I'll respin immediately since it only changes the commit message. Paolo
[Qemu-devel] [PATCH 1/3] sysfw: remove read-only pc_sysfw_flash_vs_rom_bug_compatible
The variable is not written anymore.
Signed-off-by: Paolo Bonzini pbonz...@redhat.com
---
hw/block/pc_sysfw.c | 26 +-
1 file changed, 1 insertion(+), 25 deletions(-)
diff --git a/hw/block/pc_sysfw.c b/hw/block/pc_sysfw.c
index 412d1b0..c6d4be4 100644
--- a/hw/block/pc_sysfw.c
+++ b/hw/block/pc_sysfw.c
@@ -199,12 +199,6 @@ static void old_pc_system_rom_init(MemoryRegion
*rom_memory, bool isapc_ram_fw)
bios);
}
-/*
- * Bug-compatible flash vs. ROM selection enabled?
- * A few older machines enable this.
- */
-bool pc_sysfw_flash_vs_rom_bug_compatible;
-
void pc_system_firmware_init(MemoryRegion *rom_memory)
{
DriveInfo *pflash_drv;
@@ -222,25 +216,7 @@ void pc_system_firmware_init(MemoryRegion *rom_memory)
pflash_drv = drive_get(IF_PFLASH, 0, 0);
-if (pc_sysfw_flash_vs_rom_bug_compatible) {
-/*
- * This is a Bad Idea, because it makes enabling/disabling KVM
- * guest-visible. Do it only in bug-compatibility mode.
- */
-if (kvm_enabled()) {
-if (pflash_drv != NULL) {
-fprintf(stderr, qemu: pflash cannot be used with kvm
enabled\n);
-exit(1);
-} else {
-/* In old pc_sysfw_flash_vs_rom_bug_compatible mode, we assume
- * that KVM cannot execute from device memory. In this case, we
- * use old rom based firmware initialization for KVM. But,
since
- * this is different from non-kvm mode, this behavior is
- * undesirable */
-sysfw_dev-rom_only = 1;
-}
-}
-} else if (pflash_drv == NULL) {
+if (pflash_drv == NULL) {
/* When a pflash drive is not found, use rom-mode */
sysfw_dev-rom_only = 1;
} else if (kvm_enabled() !kvm_readonly_mem_enabled()) {
--
1.8.1.4
Re: [Qemu-devel] [PATCH 1/3] sysfw: remove read-only pc_sysfw_flash_vs_rom_bug_compatible
On Mon, Jun 3, 2013 at 8:19 AM, Paolo Bonzini pbonz...@redhat.com wrote:
The variable is not written anymore.
Signed-off-by: Paolo Bonzini pbonz...@redhat.com
---
hw/block/pc_sysfw.c | 26 +-
1 file changed, 1 insertion(+), 25 deletions(-)
diff --git a/hw/block/pc_sysfw.c b/hw/block/pc_sysfw.c
index 412d1b0..c6d4be4 100644
--- a/hw/block/pc_sysfw.c
+++ b/hw/block/pc_sysfw.c
@@ -199,12 +199,6 @@ static void old_pc_system_rom_init(MemoryRegion
*rom_memory, bool isapc_ram_fw)
bios);
}
-/*
- * Bug-compatible flash vs. ROM selection enabled?
- * A few older machines enable this.
- */
-bool pc_sysfw_flash_vs_rom_bug_compatible;
Hmm. I think we still need this to retain the 1.2-1.5 compatible
behavior. But, I think I maybe my kvm readonly series didn't properly
resurrect the pc_sysfw_flash_vs_rom_bug_compatible switch.
-Jordan
-
void pc_system_firmware_init(MemoryRegion *rom_memory)
{
DriveInfo *pflash_drv;
@@ -222,25 +216,7 @@ void pc_system_firmware_init(MemoryRegion *rom_memory)
pflash_drv = drive_get(IF_PFLASH, 0, 0);
-if (pc_sysfw_flash_vs_rom_bug_compatible) {
-/*
- * This is a Bad Idea, because it makes enabling/disabling KVM
- * guest-visible. Do it only in bug-compatibility mode.
- */
-if (kvm_enabled()) {
-if (pflash_drv != NULL) {
-fprintf(stderr, qemu: pflash cannot be used with kvm
enabled\n);
-exit(1);
-} else {
-/* In old pc_sysfw_flash_vs_rom_bug_compatible mode, we
assume
- * that KVM cannot execute from device memory. In this case,
we
- * use old rom based firmware initialization for KVM. But,
since
- * this is different from non-kvm mode, this behavior is
- * undesirable */
-sysfw_dev-rom_only = 1;
-}
-}
-} else if (pflash_drv == NULL) {
+if (pflash_drv == NULL) {
/* When a pflash drive is not found, use rom-mode */
sysfw_dev-rom_only = 1;
} else if (kvm_enabled() !kvm_readonly_mem_enabled()) {
--
1.8.1.4
Re: [Qemu-devel] [PATCH 1/3] sysfw: remove read-only pc_sysfw_flash_vs_rom_bug_compatible
Il 03/06/2013 22:36, Jordan Justen ha scritto: On Mon, Jun 3, 2013 at 8:19 AM, Paolo Bonzini pbonz...@redhat.com wrote: The variable is not written anymore. Signed-off-by: Paolo Bonzini pbonz...@redhat.com --- hw/block/pc_sysfw.c | 26 +- 1 file changed, 1 insertion(+), 25 deletions(-) diff --git a/hw/block/pc_sysfw.c b/hw/block/pc_sysfw.c index 412d1b0..c6d4be4 100644 --- a/hw/block/pc_sysfw.c +++ b/hw/block/pc_sysfw.c @@ -199,12 +199,6 @@ static void old_pc_system_rom_init(MemoryRegion *rom_memory, bool isapc_ram_fw) bios); } -/* - * Bug-compatible flash vs. ROM selection enabled? - * A few older machines enable this. - */ -bool pc_sysfw_flash_vs_rom_bug_compatible; Hmm. I think we still need this to retain the 1.2-1.5 compatible behavior. But, I think I maybe my kvm readonly series didn't properly resurrect the pc_sysfw_flash_vs_rom_bug_compatible switch. No, we shouldn't. It only worked with TCG, and it is simpler to just document to use -pflash (instead of -bios) to run OVMF. The misfeature was dropped (with this minor backwards incompatibility) on purpose. Paolo
