[xen staging] x86/ucode: Move the CPIO path string into microcode_ops

[patchbot@xxxxxxx]

commit 921a2ba5c57d0e5fe541a1c790af302d2e0d1ad8
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Fri Oct 25 19:20:41 2024 +0100
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Tue Nov 5 23:42:30 2024 +0000

    x86/ucode: Move the CPIO path string into microcode_ops
    
    We've got a perfectly good vendor abstraction already for microcode.  No 
need
    for a second ad-hoc one in microcode_scan_module().
    
    This is in preparation to use ucode_ops.cpio_path in multiple places.
    
    These paths are only used during __init, so take the opportunity to move 
them
    into __initconst.
    
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Daniel P. Smith <dpsmith@xxxxxxxxxxxxxxxxxxxx>
---
 xen/arch/x86/cpu/microcode/amd.c     |  4 ++++
 xen/arch/x86/cpu/microcode/core.c    | 14 +++-----------
 xen/arch/x86/cpu/microcode/intel.c   |  4 ++++
 xen/arch/x86/cpu/microcode/private.h |  7 +++++++
 4 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/xen/arch/x86/cpu/microcode/amd.c b/xen/arch/x86/cpu/microcode/amd.c
index 0fe869eff1..c7a779c1d8 100644
--- a/xen/arch/x86/cpu/microcode/amd.c
+++ b/xen/arch/x86/cpu/microcode/amd.c
@@ -443,11 +443,15 @@ static struct microcode_patch *cf_check 
cpu_request_microcode(
     return patch;
 }
 
+static const char __initconst amd_cpio_path[] =
+    "kernel/x86/microcode/AuthenticAMD.bin";
+
 static const struct microcode_ops __initconst_cf_clobber amd_ucode_ops = {
     .cpu_request_microcode            = cpu_request_microcode,
     .collect_cpu_info                 = collect_cpu_info,
     .apply_microcode                  = apply_microcode,
     .compare_patch                    = compare_patch,
+    .cpio_path                        = amd_cpio_path,
 };
 
 void __init ucode_probe_amd(struct microcode_ops *ops)
diff --git a/xen/arch/x86/cpu/microcode/core.c 
b/xen/arch/x86/cpu/microcode/core.c
index 512671f622..b7c3e270e1 100644
--- a/xen/arch/x86/cpu/microcode/core.c
+++ b/xen/arch/x86/cpu/microcode/core.c
@@ -157,25 +157,19 @@ static int __init cf_check parse_ucode(const char *s)
 }
 custom_param("ucode", parse_ucode);
 
+static struct microcode_ops __ro_after_init ucode_ops;
+
 static void __init microcode_scan_module(struct boot_info *bi)
 {
     uint64_t *_blob_start;
     unsigned long _blob_size;
     struct cpio_data cd;
-    const char *p = NULL;
     int i;
 
     ucode_blob.size = 0;
     if ( !ucode_scan )
         return;
 
-    if ( boot_cpu_data.x86_vendor == X86_VENDOR_AMD )
-        p = "kernel/x86/microcode/AuthenticAMD.bin";
-    else if ( boot_cpu_data.x86_vendor == X86_VENDOR_INTEL )
-        p = "kernel/x86/microcode/GenuineIntel.bin";
-    else
-        return;
-
     /*
      * Try all modules and see whichever could be the microcode blob.
      */
@@ -194,7 +188,7 @@ static void __init microcode_scan_module(struct boot_info 
*bi)
         }
         cd.data = NULL;
         cd.size = 0;
-        cd = find_cpio_data(p, _blob_start, _blob_size);
+        cd = find_cpio_data(ucode_ops.cpio_path, _blob_start, _blob_size);
         if ( cd.data )
         {
             ucode_blob.size = cd.size;
@@ -205,8 +199,6 @@ static void __init microcode_scan_module(struct boot_info 
*bi)
     }
 }
 
-static struct microcode_ops __ro_after_init ucode_ops;
-
 static DEFINE_SPINLOCK(microcode_mutex);
 
 DEFINE_PER_CPU(struct cpu_signature, cpu_sig);
diff --git a/xen/arch/x86/cpu/microcode/intel.c 
b/xen/arch/x86/cpu/microcode/intel.c
index bad51f6472..aad6a693e8 100644
--- a/xen/arch/x86/cpu/microcode/intel.c
+++ b/xen/arch/x86/cpu/microcode/intel.c
@@ -405,11 +405,15 @@ static bool __init can_load_microcode(void)
     return !(mcu_ctrl & MCU_CONTROL_DIS_MCU_LOAD);
 }
 
+static const char __initconst intel_cpio_path[] =
+    "kernel/x86/microcode/GenuineIntel.bin";
+
 static const struct microcode_ops __initconst_cf_clobber intel_ucode_ops = {
     .cpu_request_microcode            = cpu_request_microcode,
     .collect_cpu_info                 = collect_cpu_info,
     .apply_microcode                  = apply_microcode,
     .compare_patch                    = compare_patch,
+    .cpio_path                        = intel_cpio_path,
 };
 
 void __init ucode_probe_intel(struct microcode_ops *ops)
diff --git a/xen/arch/x86/cpu/microcode/private.h 
b/xen/arch/x86/cpu/microcode/private.h
index c72f060ac3..c9dd8ba066 100644
--- a/xen/arch/x86/cpu/microcode/private.h
+++ b/xen/arch/x86/cpu/microcode/private.h
@@ -59,6 +59,13 @@ struct microcode_ops {
      */
     enum microcode_match_result (*compare_patch)(
         const struct microcode_patch *new, const struct microcode_patch *old);
+
+    /*
+     * For Linux inird microcode compatibliity.
+     *
+     * The path where this vendor's microcode can be found in CPIO.
+     */
+    const char *cpio_path;
 };
 
 /*
--
generated by git-patchbot for /home/xen/git/xen.git#staging