[tip: x86/cpu] x86/CPU/AMD: Move the DIV0 bug detection to the Zen1 init function

From: tip-bot2 for Borislav Petkov (AMD)
Date: Wed Nov 29 2023 - 06:22:49 EST


The following commit has been merged into the x86/cpu branch of tip:

Commit-ID: bfff3c6692ce64fa9d86eb829d18229c307a0855
Gitweb: https://git.kernel.org/tip/bfff3c6692ce64fa9d86eb829d18229c307a0855
Author: Borislav Petkov (AMD) <bp@xxxxxxxxx>
AuthorDate: Wed, 01 Nov 2023 12:52:01 +01:00
Committer: Borislav Petkov (AMD) <bp@xxxxxxxxx>
CommitterDate: Wed, 29 Nov 2023 12:12:42 +01:00

x86/CPU/AMD: Move the DIV0 bug detection to the Zen1 init function

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Reviewed-by: Nikolay Borisov <nik.borisov@xxxxxxxx>
Link: http://lore.kernel.org/r/20231120104152.13740-9-bp@xxxxxxxxx
---
arch/x86/kernel/cpu/amd.c | 13 +++----------
1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 3c3b4c1..13ad44b 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -70,10 +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_div0[] =
- AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x00, 0x0, 0x2f, 0xf),
- AMD_MODEL_RANGE(0x17, 0x50, 0x0, 0x5f, 0xf));
-
static const int amd_erratum_1485[] =
AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x19, 0x10, 0x0, 0x1f, 0xf),
AMD_MODEL_RANGE(0x19, 0x60, 0x0, 0xaf, 0xf));
@@ -1030,6 +1026,9 @@ static void init_amd_zen(struct cpuinfo_x86 *c)
if (!cpu_has(c, X86_FEATURE_CPB))
set_cpu_cap(c, X86_FEATURE_CPB);
}
+
+ pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
+ setup_force_cpu_bug(X86_BUG_DIV0);
}

static bool cpu_has_zenbleed_microcode(void)
@@ -1067,7 +1066,6 @@ static void zen2_zenbleed_check(struct cpuinfo_x86 *c)
} else {
msr_clear_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
}
-
}

static void init_amd_zen2(struct cpuinfo_x86 *c)
@@ -1219,11 +1217,6 @@ static void init_amd(struct cpuinfo_x86 *c)
cpu_has(c, X86_FEATURE_AUTOIBRS))
WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS));

- 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);
- }
-
if (!cpu_has(c, X86_FEATURE_HYPERVISOR) &&
cpu_has_amd_erratum(c, amd_erratum_1485))
msr_set_bit(MSR_ZEN4_BP_CFG, MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT);