[PATCH] thermal: intel: Don't set HFI status bit to 1

From: Srinivas Pandruvada
Date: Tue Dec 13 2022 - 21:07:35 EST


When CPU doesn't support HFI (Hardware Feedback Interface), don't include
BIT 26 in the mask to prevent clearing. otherwise this results in:
unchecked MSR access error: WRMSR to 0x1b1
(tried to write 0x0000000004000aa8)
at rIP: 0xffffffff8b8559fe (throttle_active_work+0xbe/0x1b0)

Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Fixes: 6fe1e64b6026 ("thermal: intel: Prevent accidental clearing of HFI status")
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
drivers/thermal/intel/therm_throt.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/thermal/intel/therm_throt.c b/drivers/thermal/intel/therm_throt.c
index 4bb7fddaa143..2e22bb82b738 100644
--- a/drivers/thermal/intel/therm_throt.c
+++ b/drivers/thermal/intel/therm_throt.c
@@ -194,7 +194,7 @@ static const struct attribute_group thermal_attr_group = {
#define THERM_STATUS_PROCHOT_LOG BIT(1)

#define THERM_STATUS_CLEAR_CORE_MASK (BIT(1) | BIT(3) | BIT(5) | BIT(7) | BIT(9) | BIT(11) | BIT(13) | BIT(15))
-#define THERM_STATUS_CLEAR_PKG_MASK (BIT(1) | BIT(3) | BIT(5) | BIT(7) | BIT(9) | BIT(11) | BIT(26))
+#define THERM_STATUS_CLEAR_PKG_MASK (BIT(1) | BIT(3) | BIT(5) | BIT(7) | BIT(9) | BIT(11))

/*
* Clear the bits in package thermal status register for bit = 1
@@ -211,6 +211,9 @@ void thermal_clear_package_intr_status(int level, u64 bit_mask)
} else {
msr = MSR_IA32_PACKAGE_THERM_STATUS;
msr_val = THERM_STATUS_CLEAR_PKG_MASK;
+ if (boot_cpu_has(X86_FEATURE_HFI))
+ msr_val |= BIT(26);
+
}

msr_val &= ~bit_mask;
--
2.31.1