This is a note to let you know that I've just added the patch titled
x86/cpu/vfm: Add/initialize x86_vfm field to struct cpuinfo_x86
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-cpu-vfm-add-initialize-x86_vfm-field-to-struct-c.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit ada5574116ee624d90d514b113a3594f2fef33c0
Author: Tony Luck <tony.luck@xxxxxxxxx>
Date: Tue Apr 16 14:19:03 2024 -0700
x86/cpu/vfm: Add/initialize x86_vfm field to struct cpuinfo_x86
[ Upstream commit a9d0adce69075192961f3be466c4810a21b7bc9e ]
Refactor struct cpuinfo_x86 so that the vendor, family, and model
fields are overlaid in a union with a 32-bit field that combines
all three (together with a one byte reserved field in the upper
byte).
This will make it easy, cheap, and reliable to check all three
values at once.
See
https://lore.kernel.org/r/Zgr6kT8oULbnmEXx@agluck-desk3
for why the ordering is (low-to-high bits):
(vendor, family, model)
[ bp: Move comments over the line, add the backstory about the
particular order of the fields. ]
Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240416211941.9369-2-tony.luck@xxxxxxxxx
Stable-dep-of: c9a4b55431e5 ("x86/cpu: Add Lunar Lake to list of CPUs with a broken MONITOR implementation")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 6e775303d687..428348e7f06c 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -81,9 +81,23 @@ extern u16 __read_mostly tlb_lld_1g[NR_INFO];
*/
struct cpuinfo_x86 {
- __u8 x86; /* CPU family */
- __u8 x86_vendor; /* CPU vendor */
- __u8 x86_model;
+ union {
+ /*
+ * The particular ordering (low-to-high) of (vendor,
+ * family, model) is done in case range of models, like
+ * it is usually done on AMD, need to be compared.
+ */
+ struct {
+ __u8 x86_model;
+ /* CPU family */
+ __u8 x86;
+ /* CPU vendor */
+ __u8 x86_vendor;
+ __u8 x86_reserved;
+ };
+ /* combined vendor, family, model */
+ __u32 x86_vfm;
+ };
__u8 x86_stepping;
#ifdef CONFIG_X86_64
/* Number of 4K pages in DTLB/ITLB combined(in pages): */
