ARM: ACPI: fix the AML ID format for CPU devices
PATCH 1/1 ARM: ACPI: fix the AML ID format for CPU devices
Current QEMU will stall guest VM booting under ACPI mode when vcpu count is >= 12. Analyzing the booting log, it turns out that DSDT table can't be loaded correctly due to "Invalid character(s) in name (0x62303043),
repaired: [C00*]". This is because existing QEMU uses a lower case AML ID for CPU devices (e.g. C000, C001, ..., C00a, C00b). The ACPI code inside guest VM detects this lower case character as an invalid character (see acpi_ut_valid_acpi_char() in drivers/acpi/acpica/utstring.c file) and converts it to "*". This causes duplicated IDs (i.e. "C00a" ==>"C00*" and "C00b" ==> "C00*"). So ACPI refuses to load the table.
This patch fixes the problem by changing the format with a upper case character. It matches the CPU ID formats used in other parts of QEMU code.
--- hw/arm/virt-acpi-build.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
hw/arm/virt-acpi-build.c +1 -1
@@ -53,7 +53,7 @@ static void acpi_dsdt_add_cpus(Aml *scope, int smp_cpus)uint16_t i;for (i =0 ; i < smp_cpus; i++) { -Aml *dev =aml_device ("C%03x" , i); +Aml *dev =aml_device ("C%.03X" , i);aml_append (dev,aml_name_decl ("_HID" ,aml_string ("ACPI0007" )));aml_append (dev,aml_name_decl ("_UID" ,aml_int (i)));aml_append (scope, dev);
Signature · 1 line
2.7.4
Quoted 26 lines · Wei Huang
Current QEMU will stall guest VM booting under ACPI mode when vcpu count is >= 12. Analyzing the booting log, it turns out that DSDT table can't be loaded correctly due to "Invalid character(s) in name (
0x62303043),
repaired: [C00*]". This is because existing QEMU uses a lower case AML ID for CPU devices (e.g. C000, C001, ..., C00a, C00b). The ACPI code inside guest VM detects this lower case character as an invalid character (seeacpi_ut_valid_acpi_char()indrivers/acpi/acpica/utstring.cfile) and converts it to "*". This causes duplicated IDs (i.e. "C00a" ==>"C00*" and "C00b" ==> "C00*"). So ACPI refuses to load the table.This patch fixes the problem by changing the format with a upper case character. It matches the CPU ID formats used in other parts of QEMU code.
Reported-by Eric Auger <[email protected]>Signed-off-by Wei Huang <[email protected]>--- hw/arm/virt-acpi-build.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)hw/arm/virt-acpi-build.c +0
-0
hw/arm/virt-acpi-build.c static void acpi_dsdt_add_cpus(Aml *scope, int smp_cpus) · line 59
Quoted 8 lines
hw/arm/virt-acpi-build.c +1
-1@@ -53,7 +53,7 @@ static void acpi_dsdt_add_cpus(Aml *scope, int smp_cpus)uint16_t i;for (i =0 ; i < smp_cpus; i++) { -Aml *dev =aml_device ("C%03x" , i); +Aml *dev =aml_device ("C%.03X" , i);aml_append (dev,aml_name_decl ("_HID" ,aml_string ("ACPI0007" )));aml_append (dev,aml_name_decl ("_UID" ,aml_int (i)));aml_append (scope, dev);
Thanks,
Signature · 1 line
Shannon
Hi Wei,
Quoted 26 lines · Wei Huang
Current QEMU will stall guest VM booting under ACPI mode when vcpu count is >= 12. Analyzing the booting log, it turns out that DSDT table can't be loaded correctly due to "Invalid character(s) in name (
0x62303043),
repaired: [C00*]". This is because existing QEMU uses a lower case AML ID for CPU devices (e.g. C000, C001, ..., C00a, C00b). The ACPI code inside guest VM detects this lower case character as an invalid character (seeacpi_ut_valid_acpi_char()indrivers/acpi/acpica/utstring.cfile) and converts it to "*". This causes duplicated IDs (i.e. "C00a" ==>"C00*" and "C00b" ==> "C00*"). So ACPI refuses to load the table.This patch fixes the problem by changing the format with a upper case character. It matches the CPU ID formats used in other parts of QEMU code.
Reported-by Eric Auger <[email protected]>Signed-off-by Wei Huang <[email protected]>--- hw/arm/virt-acpi-build.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)hw/arm/virt-acpi-build.c +0
-0
hw/arm/virt-acpi-build.c static void acpi_dsdt_add_cpus(Aml *scope, int smp_cpus) · line 59
Quoted 8 lines
hw/arm/virt-acpi-build.c +1
-1@@ -53,7 +53,7 @@ static void acpi_dsdt_add_cpus(Aml *scope, int smp_cpus)uint16_t i;for (i =0 ; i < smp_cpus; i++) { -Aml *dev =aml_device ("C%03x" , i); +Aml *dev =aml_device ("C%.03X" , i);aml_append (dev,aml_name_decl ("_HID" ,aml_string ("ACPI0007" )));aml_append (dev,aml_name_decl ("_UID" ,aml_int (i)));aml_append (scope, dev);
Tested on Cavium ThunderX.
Many thanks!
Eric
Quoted 25 lines · Wei Huang
Current QEMU will stall guest VM booting under ACPI mode when vcpu count is >= 12. Analyzing the booting log, it turns out that DSDT table can't be loaded correctly due to "Invalid character(s) in name (
0x62303043),
repaired: [C00*]". This is because existing QEMU uses a lower case AML ID for CPU devices (e.g. C000, C001, ..., C00a, C00b). The ACPI code inside guest VM detects this lower case character as an invalid character (seeacpi_ut_valid_acpi_char()indrivers/acpi/acpica/utstring.cfile) and converts it to "*". This causes duplicated IDs (i.e. "C00a" ==>"C00*" and "C00b" ==> "C00*"). So ACPI refuses to load the table.This patch fixes the problem by changing the format with a upper case character. It matches the CPU ID formats used in other parts of QEMU code.
Reported-by Eric Auger <[email protected]>Signed-off-by Wei Huang <[email protected]>--- hw/arm/virt-acpi-build.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)hw/arm/virt-acpi-build.c +0
-0
hw/arm/virt-acpi-build.c static void acpi_dsdt_add_cpus(Aml *scope, int smp_cpus) · line 59
Quoted 8 lines
hw/arm/virt-acpi-build.c +1
-1@@ -53,7 +53,7 @@ static void acpi_dsdt_add_cpus(Aml *scope, int smp_cpus)uint16_t i;for (i =0 ; i < smp_cpus; i++) { -Aml *dev =aml_device ("C%03x" , i); +Aml *dev =aml_device ("C%.03X" , i);aml_append (dev,aml_name_decl ("_HID" ,aml_string ("ACPI0007" )));aml_append (dev,aml_name_decl ("_UID" ,aml_int (i)));aml_append (scope, dev);
I see this is the format we use in hw/acpi/cpu.c, but why do we say "%.03X" rather than "%.3X" ? The two mean the same thing but one has a pointless extra 0 in the precision-specifier, as far as I can see...
Anyway, applied to target-arm.next.
thanks
-- PMM