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[PATCH 07/13] x86/CPU/AMD: Move Zenbleed check to the Zen2 init function

Borislav Petkov posted 13 patches 2 years ago
[PATCH 07/13] x86/CPU/AMD: Move Zenbleed check to the Zen2 init function
Posted by Borislav Petkov 2 years ago 
From: "Borislav Petkov (AMD)" <bp@alien8.de>

Prefix it properly so that it is clear which generation it is dealing
with.

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
---
 arch/x86/kernel/cpu/amd.c | 70 +++++++++++++++++----------------------
 1 file changed, 30 insertions(+), 40 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 8d90f5f6b0d9..7cbb108afaf4 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -70,12 +70,6 @@ static const int amd_erratum_383[] =
 static const int amd_erratum_1054[] =
 	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf));
 
-static const int amd_zenbleed[] =
-	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x30, 0x0, 0x4f, 0xf),
-			   AMD_MODEL_RANGE(0x17, 0x60, 0x0, 0x7f, 0xf),
-			   AMD_MODEL_RANGE(0x17, 0x90, 0x0, 0x91, 0xf),
-			   AMD_MODEL_RANGE(0x17, 0xa0, 0x0, 0xaf, 0xf));
-
 static const int amd_div0[] =
 	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x00, 0x0, 0x2f, 0xf),
 			   AMD_MODEL_RANGE(0x17, 0x50, 0x0, 0x5f, 0xf));
@@ -1039,33 +1033,6 @@ static void init_amd_zen(struct cpuinfo_x86 *c)
 
 }
 
-static void init_amd_zen2(struct cpuinfo_x86 *c)
-{
-	init_amd_zen_common();
-	init_spectral_chicken(c);
-	fix_erratum_1386(c);
-}
-
-static void init_amd_zen3(struct cpuinfo_x86 *c)
-{
-	init_amd_zen_common();
-
-	if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
-		/*
-		 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
-		 * Branch Type Confusion, but predate the allocation of the
-		 * BTC_NO bit.
-		 */
-		if (!cpu_has(c, X86_FEATURE_BTC_NO))
-			set_cpu_cap(c, X86_FEATURE_BTC_NO);
-	}
-}
-
-static void init_amd_zen4(struct cpuinfo_x86 *c)
-{
-	init_amd_zen_common();
-}
-
 static bool cpu_has_zenbleed_microcode(void)
 {
 	u32 good_rev = 0;
@@ -1087,11 +1054,8 @@ static bool cpu_has_zenbleed_microcode(void)
 	return true;
 }
 
-static void zenbleed_check(struct cpuinfo_x86 *c)
+static void zen2_zenbleed_check(struct cpuinfo_x86 *c)
 {
-	if (!cpu_has_amd_erratum(c, amd_zenbleed))
-		return;
-
 	if (cpu_has(c, X86_FEATURE_HYPERVISOR))
 		return;
 
@@ -1106,6 +1070,34 @@ static void zenbleed_check(struct cpuinfo_x86 *c)
 	}
 }
 
+static void init_amd_zen2(struct cpuinfo_x86 *c)
+{
+	init_amd_zen_common();
+	init_spectral_chicken(c);
+	fix_erratum_1386(c);
+	zen2_zenbleed_check(c);
+}
+
+static void init_amd_zen3(struct cpuinfo_x86 *c)
+{
+	init_amd_zen_common();
+
+	if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
+		/*
+		 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
+		 * Branch Type Confusion, but predate the allocation of the
+		 * BTC_NO bit.
+		 */
+		if (!cpu_has(c, X86_FEATURE_BTC_NO))
+			set_cpu_cap(c, X86_FEATURE_BTC_NO);
+	}
+}
+
+static void init_amd_zen4(struct cpuinfo_x86 *c)
+{
+	init_amd_zen_common();
+}
+
 static void init_amd(struct cpuinfo_x86 *c)
 {
 	u64 vm_cr;
@@ -1227,8 +1219,6 @@ static void init_amd(struct cpuinfo_x86 *c)
 	    cpu_has(c, X86_FEATURE_AUTOIBRS))
 		WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS));
 
-	zenbleed_check(c);
-
 	if (cpu_has_amd_erratum(c, amd_div0)) {
 		pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
 		setup_force_cpu_bug(X86_BUG_DIV0);
@@ -1390,7 +1380,7 @@ static void zenbleed_check_cpu(void *unused)
 {
 	struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
 
-	zenbleed_check(c);
+	zen2_zenbleed_check(c);
 }
 
 void amd_check_microcode(void)
-- 
2.42.0.rc0.25.ga82fb66fed25
Re: [PATCH 07/13] x86/CPU/AMD: Move Zenbleed check to the Zen2 init function
Posted by Nikolay Borisov 2 years ago 

On 20.11.23 г. 12:41 ч., Borislav Petkov wrote:
> From: "Borislav Petkov (AMD)" <bp@alien8.de>
> 
> Prefix it properly so that it is clear which generation it is dealing
> with.
> 
> No functional changes.
> 
> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
> ---
>   arch/x86/kernel/cpu/amd.c | 70 +++++++++++++++++----------------------
>   1 file changed, 30 insertions(+), 40 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
> index 8d90f5f6b0d9..7cbb108afaf4 100644
> --- a/arch/x86/kernel/cpu/amd.c
> +++ b/arch/x86/kernel/cpu/amd.c
> @@ -70,12 +70,6 @@ static const int amd_erratum_383[] =
>   static const int amd_erratum_1054[] =
>   	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf));
>   
> -static const int amd_zenbleed[] =
> -	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x30, 0x0, 0x4f, 0xf),
> -			   AMD_MODEL_RANGE(0x17, 0x60, 0x0, 0x7f, 0xf),
> -			   AMD_MODEL_RANGE(0x17, 0x90, 0x0, 0x91, 0xf),
> -			   AMD_MODEL_RANGE(0x17, 0xa0, 0x0, 0xaf, 0xf));
> -
>   static const int amd_div0[] =
>   	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x00, 0x0, 0x2f, 0xf),
>   			   AMD_MODEL_RANGE(0x17, 0x50, 0x0, 0x5f, 0xf));
> @@ -1039,33 +1033,6 @@ static void init_amd_zen(struct cpuinfo_x86 *c)
>   
>   }
>   
> -static void init_amd_zen2(struct cpuinfo_x86 *c)
> -{
> -	init_amd_zen_common();
> -	init_spectral_chicken(c);
> -	fix_erratum_1386(c);
> -}
> -
> -static void init_amd_zen3(struct cpuinfo_x86 *c)
> -{
> -	init_amd_zen_common();
> -
> -	if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
> -		/*
> -		 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
> -		 * Branch Type Confusion, but predate the allocation of the
> -		 * BTC_NO bit.
> -		 */
> -		if (!cpu_has(c, X86_FEATURE_BTC_NO))
> -			set_cpu_cap(c, X86_FEATURE_BTC_NO);
> -	}
> -}
> -
> -static void init_amd_zen4(struct cpuinfo_x86 *c)
> -{
> -	init_amd_zen_common();
> -}

nit:  If you initially introduced the zen-specific functions right after 
zenbleed_check you would have avoided the function move in this patch 
which would have reduced the overall diff.

<snip>
Re: [PATCH 07/13] x86/CPU/AMD: Move Zenbleed check to the Zen2 init function
Posted by Borislav Petkov 2 years ago 
On Mon, Nov 20, 2023 at 02:53:54PM +0200, Nikolay Borisov wrote:
> nit:  If you initially introduced the zen-specific functions right after
> zenbleed_check you would have avoided the function move in this patch which
> would have reduced the overall diff.

Yap, done, good point.

And thanks for the review.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette
[tip: x86/cpu] x86/CPU/AMD: Move Zenbleed check to the Zen2 init function
Posted by tip-bot2 for Borislav Petkov (AMD) 2 years ago 
The following commit has been merged into the x86/cpu branch of tip:

Commit-ID:     f69759be251dce722942594fbc62e53a40822a82
Gitweb:        https://git.kernel.org/tip/f69759be251dce722942594fbc62e53a40822a82
Author:        Borislav Petkov (AMD) <bp@alien8.de>
AuthorDate:    Wed, 01 Nov 2023 12:38:35 +01:00
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 29 Nov 2023 12:12:34 +01:00

x86/CPU/AMD: Move Zenbleed check to the Zen2 init function

Prefix it properly so that it is clear which generation it is dealing
with.

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: http://lore.kernel.org/r/20231120104152.13740-8-bp@alien8.de
---
 arch/x86/kernel/cpu/amd.c | 16 +++-------------
 1 file changed, 3 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index f53e0a2..3c3b4c1 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -70,12 +70,6 @@ static const int amd_erratum_383[] =
 static const int amd_erratum_1054[] =
 	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf));
 
-static const int amd_zenbleed[] =
-	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x30, 0x0, 0x4f, 0xf),
-			   AMD_MODEL_RANGE(0x17, 0x60, 0x0, 0x7f, 0xf),
-			   AMD_MODEL_RANGE(0x17, 0x90, 0x0, 0x91, 0xf),
-			   AMD_MODEL_RANGE(0x17, 0xa0, 0x0, 0xaf, 0xf));
-
 static const int amd_div0[] =
 	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x00, 0x0, 0x2f, 0xf),
 			   AMD_MODEL_RANGE(0x17, 0x50, 0x0, 0x5f, 0xf));
@@ -1059,11 +1053,8 @@ static bool cpu_has_zenbleed_microcode(void)
 	return true;
 }
 
-static void zenbleed_check(struct cpuinfo_x86 *c)
+static void zen2_zenbleed_check(struct cpuinfo_x86 *c)
 {
-	if (!cpu_has_amd_erratum(c, amd_zenbleed))
-		return;
-
 	if (cpu_has(c, X86_FEATURE_HYPERVISOR))
 		return;
 
@@ -1084,6 +1075,7 @@ static void init_amd_zen2(struct cpuinfo_x86 *c)
 	init_amd_zen_common();
 	init_spectral_chicken(c);
 	fix_erratum_1386(c);
+	zen2_zenbleed_check(c);
 }
 
 static void init_amd_zen3(struct cpuinfo_x86 *c)
@@ -1227,8 +1219,6 @@ static void init_amd(struct cpuinfo_x86 *c)
 	    cpu_has(c, X86_FEATURE_AUTOIBRS))
 		WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS));
 
-	zenbleed_check(c);
-
 	if (cpu_has_amd_erratum(c, amd_div0)) {
 		pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
 		setup_force_cpu_bug(X86_BUG_DIV0);
@@ -1393,7 +1383,7 @@ static void zenbleed_check_cpu(void *unused)
 {
 	struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
 
-	zenbleed_check(c);
+	zen2_zenbleed_check(c);
 }
 
 void amd_check_microcode(void)

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