From 2bc6b218717b9d08f466f88209251d54bc09b207 Mon Sep 17 00:00:00 2001 From: Fuad Tabba Date: Tue, 22 Sep 2026 19:14:30 +0100 Subject: arm64/boot: Disable trapping of PMZR_EL0 writes to EL2 __init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2. PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a write from EL0 reaches the trap and takes the host down without a panic message. Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already does for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9 bits. Fixes: 858c7bfcb35e1 ("arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9") Cc: stable@vger.kernel.org Signed-off-by: Fuad Tabba Reviewed-by: Anshuman Khandual Reviewed-by: Oliver Upton Signed-off-by: Will Deacon --- include/uapi/asm-generic/mman.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) create mode 100644 include/uapi/asm-generic/mman.h (limited to 'include/uapi/asm-generic/mman.h') diff --git a/include/uapi/asm-generic/mman.h b/include/uapi/asm-generic/mman.h new file mode 100644 index 000000000..5e3d61ddb --- /dev/null +++ b/include/uapi/asm-generic/mman.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef __ASM_GENERIC_MMAN_H +#define __ASM_GENERIC_MMAN_H + +#include + +#define MAP_GROWSDOWN 0x0100 /* stack-like segment */ +#define MAP_DENYWRITE 0x0800 /* ETXTBSY */ +#define MAP_EXECUTABLE 0x1000 /* mark it as an executable */ +#define MAP_LOCKED 0x2000 /* pages are locked */ +#define MAP_NORESERVE 0x4000 /* don't check for reservations */ + +/* + * Bits [26:31] are reserved, see asm-generic/hugetlb_encode.h + * for MAP_HUGETLB usage + */ + +#define MCL_CURRENT 1 /* lock all current mappings */ +#define MCL_FUTURE 2 /* lock all future mappings */ +#define MCL_ONFAULT 4 /* lock all pages that are faulted in */ + +#define SHADOW_STACK_SET_TOKEN (1ULL << 0) /* Set up a restore token in the shadow stack */ +#define SHADOW_STACK_SET_MARKER (1ULL << 1) /* Set up a top of stack marker in the shadow stack */ + + +#endif /* __ASM_GENERIC_MMAN_H */ -- cgit v1.3.1