[PATCH v18 01/14] arm64/gcs: Ensure FGTs for EL1 GCS instructions are disabled
Mark Brown <[email protected]> Mon, 03 Aug 2026 23:56:46 +0100
| Newsgroups | org.kernel.vger.linux-kselftest,dev.linux.lists.kvmarm,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-doc,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
The initial EL2 setup for GCS did not include disabling of EL1 usage of
GCS instructions, also disable these traps.
Fixes: ff5181d8a2a8 ("arm64/gcs: Provide basic EL2 setup to allow GCS usage at EL0 and EL1")
Signed-off-by: Mark Brown <[email protected]>
---
arch/arm64/include/asm/el2_setup.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
index aa8ec9df8024..d308c6e6757d 100644
--- a/arch/arm64/include/asm/el2_setup.h
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -393,6 +393,11 @@
orr x0, x0, #HFGRTR_EL2_nGCS_EL1_MASK
orr x0, x0, #HFGRTR_EL2_nGCS_EL0_MASK
+ /* Disable traps of GCS instructions at EL1 */
+ orr x2, x2, #HFGITR_EL2_nGCSEPP_MASK
+ orr x2, x2, #HFGITR_EL2_nGCSSTR_EL1_MASK
+ orr x2, x2, #HFGITR_EL2_nGCSPUSHM_EL1_MASK
+
.Lskip_gce_fgt_\@:
.Lset_fgt_\@:
--
2.47.3