[V2,12/37] x86/microcode/intel: Simplify and rename generic_load_microcode()

Message ID 20230812195728.246048244@linutronix.de
State New
Headers
Series x86/microcode: Cleanup and late loading enhancements |

Commit Message

Thomas Gleixner Aug. 12, 2023, 7:58 p.m. UTC
  so it becomes less obfuscated and rename it because there is nothing
generic about it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/kernel/cpu/microcode/intel.c |   47 ++++++++++++----------------------
 1 file changed, 17 insertions(+), 30 deletions(-)
  

Comments

Borislav Petkov Aug. 14, 2023, 1:19 p.m. UTC | #1
On Sat, Aug 12, 2023 at 09:58:55PM +0200, Thomas Gleixner wrote:
> @@ -645,14 +632,12 @@ static enum ucode_state apply_microcode_
>  	return ret;
>  }
>  
> -static enum ucode_state generic_load_microcode(int cpu, struct iov_iter *iter)
> +static enum ucode_state read_ucode_intel(int cpu, struct iov_iter *iter)

I'd do this ontop:

---
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index 2b49637778be..a45ecbab5137 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -632,7 +632,7 @@ static enum ucode_state apply_microcode_intel(int cpu)
 	return ret;
 }
 
-static enum ucode_state read_ucode_intel(int cpu, struct iov_iter *iter)
+static enum ucode_state parse_microcode_blobs(int cpu, struct iov_iter *iter)
 {
 	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 	unsigned int curr_mc_size = 0, new_mc_size = 0;
@@ -758,7 +758,7 @@ static enum ucode_state request_microcode_fw(int cpu, struct device *device)
 	kvec.iov_base = (void *)firmware->data;
 	kvec.iov_len = firmware->size;
 	iov_iter_kvec(&iter, ITER_SOURCE, &kvec, 1, firmware->size);
-	ret = read_ucode_intel(cpu, &iter);
+	ret = parse_microcode_blobs(cpu, &iter);
 
 	release_firmware(firmware);
  
Thomas Gleixner Aug. 14, 2023, 2:40 p.m. UTC | #2
On Mon, Aug 14 2023 at 15:19, Borislav Petkov wrote:
> On Sat, Aug 12, 2023 at 09:58:55PM +0200, Thomas Gleixner wrote:
>> @@ -645,14 +632,12 @@ static enum ucode_state apply_microcode_
>>  	return ret;
>>  }
>>  
>> -static enum ucode_state generic_load_microcode(int cpu, struct iov_iter *iter)
>> +static enum ucode_state read_ucode_intel(int cpu, struct iov_iter *iter)
>
> I'd do this ontop:

Sure.
  

Patch

--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -240,19 +240,6 @@  int intel_microcode_sanity_check(void *m
 }
 EXPORT_SYMBOL_GPL(intel_microcode_sanity_check);
 
-/*
- * Returns 1 if update has been found, 0 otherwise.
- */
-static int has_newer_microcode(void *mc, unsigned int csig, int cpf, int new_rev)
-{
-	struct microcode_header_intel *mc_hdr = mc;
-
-	if (mc_hdr->rev <= new_rev)
-		return 0;
-
-	return intel_find_matching_signature(mc, csig, cpf);
-}
-
 static void save_microcode_patch(void *data, unsigned int size)
 {
 	struct microcode_header_intel *p;
@@ -645,14 +632,12 @@  static enum ucode_state apply_microcode_
 	return ret;
 }
 
-static enum ucode_state generic_load_microcode(int cpu, struct iov_iter *iter)
+static enum ucode_state read_ucode_intel(int cpu, struct iov_iter *iter)
 {
 	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 	unsigned int curr_mc_size = 0, new_mc_size = 0;
-	enum ucode_state ret = UCODE_OK;
-	int new_rev = uci->cpu_sig.rev;
+	int cur_rev = uci->cpu_sig.rev;
 	u8 *new_mc = NULL, *mc = NULL;
-	unsigned int csig, cpf;
 
 	while (iov_iter_count(iter)) {
 		struct microcode_header_intel mc_header;
@@ -669,6 +654,7 @@  static enum ucode_state generic_load_mic
 			pr_err("error! Bad data in microcode data file (totalsize too small)\n");
 			break;
 		}
+
 		data_size = mc_size - sizeof(mc_header);
 		if (data_size > iov_iter_count(iter)) {
 			pr_err("error! Bad data in microcode data file (truncated file?)\n");
@@ -691,16 +677,17 @@  static enum ucode_state generic_load_mic
 			break;
 		}
 
-		csig = uci->cpu_sig.sig;
-		cpf = uci->cpu_sig.pf;
-		if (has_newer_microcode(mc, csig, cpf, new_rev)) {
-			vfree(new_mc);
-			new_rev = mc_header.rev;
-			new_mc  = mc;
-			new_mc_size = mc_size;
-			mc = NULL;	/* trigger new vmalloc */
-			ret = UCODE_NEW;
-		}
+		if (cur_rev >= mc_header.rev)
+			continue;
+
+		if (!intel_find_matching_signature(mc, uci->cpu_sig.sig, uci->cpu_sig.pf))
+			continue;
+
+		vfree(new_mc);
+		cur_rev = mc_header.rev;
+		new_mc  = mc;
+		new_mc_size = mc_size;
+		mc = NULL;
 	}
 
 	vfree(mc);
@@ -720,9 +707,9 @@  static enum ucode_state generic_load_mic
 	save_microcode_patch(new_mc, new_mc_size);
 
 	pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
-		 cpu, new_rev, uci->cpu_sig.rev);
+		 cpu, cur_rev, uci->cpu_sig.rev);
 
-	return ret;
+	return UCODE_NEW;
 }
 
 static bool is_blacklisted(unsigned int cpu)
@@ -771,7 +758,7 @@  static enum ucode_state request_microcod
 	kvec.iov_base = (void *)firmware->data;
 	kvec.iov_len = firmware->size;
 	iov_iter_kvec(&iter, ITER_SOURCE, &kvec, 1, firmware->size);
-	ret = generic_load_microcode(cpu, &iter);
+	ret = read_ucode_intel(cpu, &iter);
 
 	release_firmware(firmware);