Mailing List Archive

Refactor microcode_update() hypercall by adding flags field.
Introduce XENPF_microcode_update2 hypercall to handle flags field.
struct xenpf_microcode_update updated to have uint32_t flags at
the end of the sturcture.

[v2]
1- Update message description to highlight interface change.
2- Removed extra empty lines.
3- removed unnecessary define.
4- Corrected long lines.
5- Removed ternary operator.
6- Introduced static ucode_update_flags, which will be used later to determine local ucode_force_flag.

Signed-off-by: Fouad Hilly <fouad.hilly@cloud.com>
---
xen/arch/x86/cpu/microcode/core.c | 14 +++++++++++---
xen/arch/x86/include/asm/microcode.h | 3 ++-
xen/arch/x86/platform_hypercall.c | 12 +++++++++++-
xen/include/public/platform.h | 6 ++++++
4 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/xen/arch/x86/cpu/microcode/core.c b/xen/arch/x86/cpu/microcode/core.c
index 1c9f66ea8a0f..99b651d8c3a1 100644
--- a/xen/arch/x86/cpu/microcode/core.c
+++ b/xen/arch/x86/cpu/microcode/core.c
@@ -40,6 +40,8 @@
#include <asm/processor.h>
#include <asm/setup.h>

+#include <public/platform.h>
+
#include "private.h"

/*
@@ -100,6 +102,8 @@ static bool ucode_in_nmi = true;

bool __read_mostly opt_ucode_allow_same;

+static unsigned int ucode_update_flags = 0;
+
/* Protected by microcode_mutex */
static struct microcode_patch *microcode_cache;

@@ -580,6 +584,7 @@ static long cf_check microcode_update_helper(void *data)
struct ucode_buf *buffer = data;
unsigned int cpu, updated;
struct microcode_patch *patch;
+ bool ucode_force_flag = ucode_update_flags == XENPF_UCODE_FLAG_FORCE_SET;

/* cpu_online_map must not change during update */
if ( !get_cpu_maps() )
@@ -633,12 +638,12 @@ static long cf_check microcode_update_helper(void *data)
microcode_cache);

if ( result != NEW_UCODE &&
- !(opt_ucode_allow_same && result == SAME_UCODE) )
+ !((opt_ucode_allow_same || ucode_force_flag) && result == SAME_UCODE) )
{
spin_unlock(&microcode_mutex);
printk(XENLOG_WARNING
"microcode: couldn't find any newer%s revision in the provided blob!\n",
- opt_ucode_allow_same ? " (or the same)" : "");
+ (opt_ucode_allow_same || ucode_force_flag) ? " (or the same)" : "");
microcode_free_patch(patch);
ret = -ENOENT;

@@ -708,7 +713,8 @@ static long cf_check microcode_update_helper(void *data)
return ret;
}

-int microcode_update(XEN_GUEST_HANDLE(const_void) buf, unsigned long len)
+int microcode_update(XEN_GUEST_HANDLE(const_void) buf,
+ unsigned long len, unsigned int flags)
{
int ret;
struct ucode_buf *buffer;
@@ -731,6 +737,8 @@ int microcode_update(XEN_GUEST_HANDLE(const_void) buf, unsigned long len)
}
buffer->len = len;

+ ucode_update_flags = flags;
+
/*
* Always queue microcode_update_helper() on CPU0. Most of the logic
* won't care, but the update of the Raw CPU policy wants to (re)run on
diff --git a/xen/arch/x86/include/asm/microcode.h b/xen/arch/x86/include/asm/microcode.h
index 8f59b20b0289..57c08205d475 100644
--- a/xen/arch/x86/include/asm/microcode.h
+++ b/xen/arch/x86/include/asm/microcode.h
@@ -22,7 +22,8 @@ struct cpu_signature {
DECLARE_PER_CPU(struct cpu_signature, cpu_sig);

void microcode_set_module(unsigned int idx);
-int microcode_update(XEN_GUEST_HANDLE(const_void) buf, unsigned long len);
+int microcode_update(XEN_GUEST_HANDLE(const_void) buf,
+ unsigned long len, unsigned int flags);
int early_microcode_init(unsigned long *module_map,
const struct multiboot_info *mbi);
int microcode_init_cache(unsigned long *module_map,
diff --git a/xen/arch/x86/platform_hypercall.c b/xen/arch/x86/platform_hypercall.c
index 95467b88ab64..3b29ede8b316 100644
--- a/xen/arch/x86/platform_hypercall.c
+++ b/xen/arch/x86/platform_hypercall.c
@@ -311,7 +311,17 @@ ret_t do_platform_op(

guest_from_compat_handle(data, op->u.microcode.data);

- ret = microcode_update(data, op->u.microcode.length);
+ ret = microcode_update(data, op->u.microcode.length, 0);
+ break;
+ }
+
+ case XENPF_microcode_update2:
+ {
+ XEN_GUEST_HANDLE(const_void) data;
+
+ guest_from_compat_handle(data, op->u.microcode.data);
+
+ ret = microcode_update(data, op->u.microcode.length, op->u.microcode.flags);
break;
}

diff --git a/xen/include/public/platform.h b/xen/include/public/platform.h
index 15777b541690..cc19b2956b46 100644
--- a/xen/include/public/platform.h
+++ b/xen/include/public/platform.h
@@ -99,6 +99,9 @@ struct xenpf_microcode_update {
/* IN variables. */
XEN_GUEST_HANDLE(const_void) data;/* Pointer to microcode data */
uint32_t length; /* Length of microcode data. */
+ uint32_t flags; /* Flags to be passed with ucode. */
+/* Force to skip microcode version check when set */
+#define XENPF_UCODE_FLAG_FORCE_SET 1
};
typedef struct xenpf_microcode_update xenpf_microcode_update_t;
DEFINE_XEN_GUEST_HANDLE(xenpf_microcode_update_t);
@@ -624,6 +627,9 @@ struct xenpf_ucode_revision {
typedef struct xenpf_ucode_revision xenpf_ucode_revision_t;
DEFINE_XEN_GUEST_HANDLE(xenpf_ucode_revision_t);

+/* Hypercall to microcode_update with flags */
+#define XENPF_microcode_update2 66
+
/*
* ` enum neg_errnoval
* ` HYPERVISOR_platform_op(const struct xen_platform_op*);
--
2.42.0