[tip: x86/cpu] x86/mm: Don't disable PCID when INVLPG has been fixed by microcode

From: tip-bot2 for Xi Ruoyao
Date: Wed Oct 02 2024 - 14:58:33 EST


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

Commit-ID: f24f669d03f884a6ef95cca84317d0f329e93961
Gitweb: https://git.kernel.org/tip/f24f669d03f884a6ef95cca84317d0f329e93961
Author: Xi Ruoyao <xry111@xxxxxxxxxxx>
AuthorDate: Wed, 22 May 2024 10:06:24 +08:00
Committer: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
CommitterDate: Wed, 02 Oct 2024 10:59:07 -07:00

x86/mm: Don't disable PCID when INVLPG has been fixed by microcode

Per the "Processor Specification Update" documentations referred by
the intel-microcode-20240312 release note, this microcode release has
fixed the issue for all affected models.

So don't disable PCID if the microcode is new enough. The precise
minimum microcode revision fixing the issue was provided by Pawan
Intel.

[ dhansen: comment and changelog tweaks ]

Signed-off-by: Xi Ruoyao <xry111@xxxxxxxxxxx>
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Acked-by: Pawan Gupta <pawan.kumar.gupta@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/all/168436059559.404.13934972543631851306.tip-bot2@tip-bot2/
Link: https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files/releases/tag/microcode-20240312
Link: https://cdrdv2.intel.com/v1/dl/getContent/740518 # RPL042, rev. 13
Link: https://cdrdv2.intel.com/v1/dl/getContent/682436 # ADL063, rev. 24
Link: https://lore.kernel.org/all/20240325231300.qrltbzf6twm43ftb@desk/
Link: https://lore.kernel.org/all/20240522020625.69418-1-xry111%40xry111.site
---
arch/x86/mm/init.c | 23 ++++++++++++++---------
1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index eb503f5..101725c 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -263,28 +263,33 @@ static void __init probe_page_size_mask(void)
}

/*
- * INVLPG may not properly flush Global entries
- * on these CPUs when PCIDs are enabled.
+ * INVLPG may not properly flush Global entries on
+ * these CPUs. New microcode fixes the issue.
*/
static const struct x86_cpu_id invlpg_miss_ids[] = {
- X86_MATCH_VFM(INTEL_ALDERLAKE, 0),
- X86_MATCH_VFM(INTEL_ALDERLAKE_L, 0),
- X86_MATCH_VFM(INTEL_ATOM_GRACEMONT, 0),
- X86_MATCH_VFM(INTEL_RAPTORLAKE, 0),
- X86_MATCH_VFM(INTEL_RAPTORLAKE_P, 0),
- X86_MATCH_VFM(INTEL_RAPTORLAKE_S, 0),
+ X86_MATCH_VFM(INTEL_ALDERLAKE, 0x2e),
+ X86_MATCH_VFM(INTEL_ALDERLAKE_L, 0x42c),
+ X86_MATCH_VFM(INTEL_ATOM_GRACEMONT, 0x11),
+ X86_MATCH_VFM(INTEL_RAPTORLAKE, 0x118),
+ X86_MATCH_VFM(INTEL_RAPTORLAKE_P, 0x4117),
+ X86_MATCH_VFM(INTEL_RAPTORLAKE_S, 0x2e),
{}
};

static void setup_pcid(void)
{
+ const struct x86_cpu_id *invlpg_miss_match;
+
if (!IS_ENABLED(CONFIG_X86_64))
return;

if (!boot_cpu_has(X86_FEATURE_PCID))
return;

- if (x86_match_cpu(invlpg_miss_ids)) {
+ invlpg_miss_match = x86_match_cpu(invlpg_miss_ids);
+
+ if (invlpg_miss_match &&
+ boot_cpu_data.microcode < invlpg_miss_match->driver_data) {
pr_info("Incomplete global flushes, disabling PCID");
setup_clear_cpu_cap(X86_FEATURE_PCID);
return;