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| author | Fuad Tabba <fuad.tabba@linux.dev> | 2026-09-22 19:14:30 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2026-09-23 12:34:30 +0000 |
| commit | 2bc6b218717b9d08f466f88209251d54bc09b207 (patch) | |
| tree | cb91c941eccb15f94cbec4e96aa3a9c8736b5d66 /include/trace/events/exceptions.h | |
| download | linux-stable-2bc6b218717b9d08f466f88209251d54bc09b207.tar.gz linux-stable-2bc6b218717b9d08f466f88209251d54bc09b207.zip | |
arm64/boot: Disable trapping of PMZR_EL0 writes to EL2grafted
__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 <fuad.tabba@linux.dev>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oliver Upton <oupton@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'include/trace/events/exceptions.h')
| -rw-r--r-- | include/trace/events/exceptions.h | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/include/trace/events/exceptions.h b/include/trace/events/exceptions.h new file mode 100644 index 000000000..a631f8de8 --- /dev/null +++ b/include/trace/events/exceptions.h @@ -0,0 +1,43 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM exceptions + +#if !defined(_TRACE_PAGE_FAULT_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_PAGE_FAULT_H + +#include <linux/tracepoint.h> + +DECLARE_EVENT_CLASS(exceptions, + + TP_PROTO(unsigned long address, struct pt_regs *regs, + unsigned long error_code), + + TP_ARGS(address, regs, error_code), + + TP_STRUCT__entry( + __field( unsigned long, address ) + __field( unsigned long, ip ) + __field( unsigned long, error_code ) + ), + + TP_fast_assign( + __entry->address = address; + __entry->ip = instruction_pointer(regs); + __entry->error_code = error_code; + ), + + TP_printk("address=%ps ip=%ps error_code=0x%lx", + (void *)__entry->address, (void *)__entry->ip, + __entry->error_code) ); + +DEFINE_EVENT(exceptions, page_fault_user, + TP_PROTO(unsigned long address, struct pt_regs *regs, unsigned long error_code), + TP_ARGS(address, regs, error_code)); +DEFINE_EVENT(exceptions, page_fault_kernel, + TP_PROTO(unsigned long address, struct pt_regs *regs, unsigned long error_code), + TP_ARGS(address, regs, error_code)); + +#endif /* _TRACE_PAGE_FAULT_H */ + +/* This part must be outside protection */ +#include <trace/define_trace.h> |