[PATCH v15 1/6] arm64/gcs: Ensure FGTs for EL1 GCS instructions are disabled
From: Mark Brown
Date: Wed Aug 20 2025 - 10:17:46 EST
The initial EL2 setup for GCS did not include disabling of EL1 usage of
GCS instructions, also disable these traps. This is the first disabling
of instruction traps, use x2 to store the value to be written.
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
arch/arm64/include/asm/el2_setup.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
index 46033027510c..0ac14ea4dbc8 100644
--- a/arch/arm64/include/asm/el2_setup.h
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -355,6 +355,10 @@
.Lskip_gce_fgt_\@:
+ orr x2, x2, #HFGITR_EL2_nGCSEPP_MASK
+ orr x2, x2, #HFGITR_EL2_nGCSSTR_EL1_MASK
+ orr x2, x2, #HFGITR_EL2_nGCSPUSHM_EL1_MASK
+
.Lset_fgt_\@:
msr_s SYS_HFGRTR_EL2, x0
msr_s SYS_HFGWTR_EL2, x0
--
2.39.5