[PATCH 5/5] x86: Add --force option to xen-ucode to override microcode version check

[Fouad Hilly]

Introduce --force option to xen-ucode to force skipping microcode version
check, which allows the user to update x86 microcode even if both versions
are the same.

Signed-off-by: Fouad Hilly <fouad.hi...@cloud.com>
---

Suggested-by: Andrew Cooper <andrew.coop...@citrix.com>
---
 tools/include/xenctrl.h   |  2 +-
 tools/libs/ctrl/xc_misc.c | 12 ++++++++++--
 tools/misc/xen-ucode.c    | 20 +++++++++++++++-----
 3 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/tools/include/xenctrl.h b/tools/include/xenctrl.h
index 2ef8b4e05422..5dbe3e63374a 100644
--- a/tools/include/xenctrl.h
+++ b/tools/include/xenctrl.h
@@ -1171,7 +1171,7 @@ typedef uint32_t xc_node_to_node_dist_t;
 int xc_physinfo(xc_interface *xch, xc_physinfo_t *info);
 int xc_cputopoinfo(xc_interface *xch, unsigned *max_cpus,
                    xc_cputopo_t *cputopo);
-int xc_microcode_update(xc_interface *xch, const void *buf, size_t len);
+int xc_microcode_update(xc_interface *xch, const void *buf, size_t len, 
uint32_t flags);
 int xc_get_cpu_version(xc_interface *xch, struct xenpf_pcpu_version *cpu_ver);
 int xc_get_ucode_revision(xc_interface *xch,
                           struct xenpf_ucode_revision *ucode_rev);
diff --git a/tools/libs/ctrl/xc_misc.c b/tools/libs/ctrl/xc_misc.c
index 5ecdfa2c7934..edce45bc2a17 100644
--- a/tools/libs/ctrl/xc_misc.c
+++ b/tools/libs/ctrl/xc_misc.c
@@ -203,7 +203,7 @@ int xc_physinfo(xc_interface *xch,
     return 0;
 }
 
-int xc_microcode_update(xc_interface *xch, const void *buf, size_t len)
+int xc_microcode_update(xc_interface *xch, const void *buf, size_t len, 
uint32_t flags)
 {
     int ret;
     struct xen_platform_op platform_op = {};
@@ -215,7 +215,15 @@ int xc_microcode_update(xc_interface *xch, const void 
*buf, size_t len)
 
     memcpy(uc, buf, len);
 
-    platform_op.cmd = XENPF_microcode_update;
+    if ( flags > XENPF_UCODE_FLAG_FORCE_NOT_SET )
+    {
+        platform_op.cmd = XENPF_microcode_update2;
+        platform_op.u.microcode.flags = flags;
+    }
+    else
+    {
+        platform_op.cmd = XENPF_microcode_update;
+    }
     platform_op.u.microcode.length = len;
     set_xen_guest_handle(platform_op.u.microcode.data, uc);
 
diff --git a/tools/misc/xen-ucode.c b/tools/misc/xen-ucode.c
index 9bde991c5df5..469ce3299381 100644
--- a/tools/misc/xen-ucode.c
+++ b/tools/misc/xen-ucode.c
@@ -13,6 +13,8 @@
 #include <xenctrl.h>
 #include <getopt.h>
 
+#include <xen/platform.h>
+
 static xc_interface *xch;
 
 static const char intel_id[] = "GenuineIntel";
@@ -21,10 +23,11 @@ static const char   amd_id[] = "AuthenticAMD";
 static void usage(const char *name)
 {
     printf("%s: Xen microcode updating tool\n"
-            "Usage: %s [<microcode file> | --show-cpu-info]\n"
+            "Usage: %s [[--force] <microcode file> | --show-cpu-info]\n"
             "\n"
             "  -h, --help            display this help and exit\n"
             "  -s, --show-cpu-info   show CPU information and exit\n"
+            "  -f, --force           force to skip micorocde version check\n"
             "\n"
             , name, name);
 }
@@ -89,11 +92,13 @@ int main(int argc, char *argv[])
     char *filename = NULL, *buf;
     size_t len;
     struct stat st;
+    uint32_t ucode_flag = XENPF_UCODE_FLAG_FORCE_NOT_SET;
     int opt;
 
     const static struct option options[] = {
         {"help", no_argument, NULL, 'h'},
         {"show-cpu-info", no_argument, NULL, 's'},
+        {"force", required_argument, NULL, 'f'},
         {NULL, no_argument, NULL, 0}
     };
 
@@ -105,10 +110,10 @@ int main(int argc, char *argv[])
         exit(1);
     }
 
-    if ( argc != 2 )
+    if ( argc < 2 || argc > 3)
         goto ext_err;
 
-    while ( (opt = getopt_long(argc, argv, "hs:", options, NULL)) != -1 )
+    while ( (opt = getopt_long(argc, argv, "hsf:", options, NULL)) != -1 )
     {
         switch (opt)
         {
@@ -120,12 +125,17 @@ int main(int argc, char *argv[])
                     goto ext_err;
                 show_curr_cpu(stdout);
                 exit(EXIT_SUCCESS);
+            case 'f':
+            ucode_flag = XENPF_UCODE_FLAG_FORCE_SET;
+                filename = optarg;
+                break;
             default:
                 goto ext_err;
         }
     }
 
-    filename = argv[1];
+    if ( argc == 2 )
+        filename = argv[1];
     if ( filename == NULL )
     {
         printf("File name error\n");
@@ -155,7 +165,7 @@ int main(int argc, char *argv[])
         exit(1);
     }
 
-    ret = xc_microcode_update(xch, buf, len);
+    ret = xc_microcode_update(xch, buf, len, ucode_flag);
     if ( ret )
     {
         fprintf(stderr, "Failed to update microcode. (err: %s)\n",
-- 
2.42.0