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 --- scripts/ksymoops/README | 7 +++++++ 1 file changed, 7 insertions(+) create mode 100644 scripts/ksymoops/README (limited to 'scripts/ksymoops/README') diff --git a/scripts/ksymoops/README b/scripts/ksymoops/README new file mode 100644 index 000000000..413043980 --- /dev/null +++ b/scripts/ksymoops/README @@ -0,0 +1,7 @@ +ksymoops has been removed from the kernel. It was always meant to be a +free standing utility, not linked to any particular kernel version. +The latest version can be found in +https://www.kernel.org/pub/linux/utils/kernel/ksymoops together with patches to +other utilities in order to give more accurate Oops debugging. + +Keith Owens Sat Jun 19 10:30:34 EST 1999 -- cgit v1.3.1