diff options
| author | Ravi Bangoria <[email protected]> | 2024-08-08 06:29:35 +0000 |
|---|---|---|
| committer | Thomas Gleixner <[email protected]> | 2024-08-08 18:02:15 +0200 |
| commit | 408eb7417a92c5354c7be34f7425b305dfe30ad9 (patch) | |
| tree | 4b48ca92bc9691ff95683a6c994def1a20df70bb | |
| parent | 350afa8a1101f62ce31bc4ed6f69cf4b90ec4fa2 (diff) | |
x86/bus_lock: Add support for AMD
Add Bus Lock Detect (called Bus Lock Trap in AMD docs) support for AMD
platforms. Bus Lock Detect is enumerated with CPUID Fn0000_0007_ECX_x0
bit [24 / BUSLOCKTRAP]. It can be enabled through MSR_IA32_DEBUGCTLMSR.
When enabled, hardware clears DR6[11] and raises a #DB exception on
occurrence of Bus Lock if CPL > 0. More detail about the feature can be
found in AMD APM[1].
[1]: AMD64 Architecture Programmer's Manual Pub. 40332, Rev. 4.07 - June
2023, Vol 2, 13.1.3.6 Bus Lock Trap
https://bugzilla.kernel.org/attachment.cgi?id=304653
Signed-off-by: Ravi Bangoria <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Tom Lendacky <[email protected]>
Link: https://lore.kernel.org/all/[email protected]
| -rw-r--r-- | Documentation/arch/x86/buslock.rst | 3 | ||||
| -rw-r--r-- | arch/x86/Kconfig | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/intel.c | 1 |
4 files changed, 5 insertions, 3 deletions
diff --git a/Documentation/arch/x86/buslock.rst b/Documentation/arch/x86/buslock.rst index 4c5a4822eeb7..31f1bfdff16f 100644 --- a/Documentation/arch/x86/buslock.rst +++ b/Documentation/arch/x86/buslock.rst @@ -26,7 +26,8 @@ Detection ========= Intel processors may support either or both of the following hardware -mechanisms to detect split locks and bus locks. +mechanisms to detect split locks and bus locks. Some AMD processors also +support bus lock detect. #AC exception for split lock detection -------------------------------------- diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 9c4e69a1ae7a..e3d53fc7419a 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2428,7 +2428,7 @@ source "kernel/livepatch/Kconfig" config X86_BUS_LOCK_DETECT bool "Split Lock Detect and Bus Lock Detect support" - depends on CPU_SUP_INTEL + depends on CPU_SUP_INTEL || CPU_SUP_AMD default y help Enable Split Lock Detect and Bus Lock Detect functionalities. diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index d4e539d4e158..a37670e1ab4d 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1832,6 +1832,8 @@ static void identify_cpu(struct cpuinfo_x86 *c) if (this_cpu->c_init) this_cpu->c_init(c); + bus_lock_init(); + /* Disable the PN if appropriate */ squash_the_stupid_serial_number(c); diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 8a483f4ad026..799f18545c6e 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -610,7 +610,6 @@ static void init_intel(struct cpuinfo_x86 *c) init_intel_misc_features(c); split_lock_init(); - bus_lock_init(); intel_init_thermal(c); } |