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/asm-generic/getorder.h | 52 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 include/asm-generic/getorder.h (limited to 'include/asm-generic/getorder.h') diff --git a/include/asm-generic/getorder.h b/include/asm-generic/getorder.h new file mode 100644 index 000000000..875ccae19 --- /dev/null +++ b/include/asm-generic/getorder.h @@ -0,0 +1,52 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_GENERIC_GETORDER_H +#define __ASM_GENERIC_GETORDER_H + +#ifndef __ASSEMBLER__ + +#include +#include + +/** + * get_order - Determine the allocation order of a memory size + * @size: The size for which to get the order + * + * Determine the allocation order of a particular sized block of memory. This + * is on a logarithmic scale, where: + * + * 0 -> 2^0 * PAGE_SIZE and below + * 1 -> 2^1 * PAGE_SIZE to 2^0 * PAGE_SIZE + 1 + * 2 -> 2^2 * PAGE_SIZE to 2^1 * PAGE_SIZE + 1 + * 3 -> 2^3 * PAGE_SIZE to 2^2 * PAGE_SIZE + 1 + * 4 -> 2^4 * PAGE_SIZE to 2^3 * PAGE_SIZE + 1 + * ... + * + * The order returned is used to find the smallest allocation granule required + * to hold an object of the specified size. + * + * The result is undefined if the size is 0. + */ +static __always_inline __attribute_const__ int get_order(unsigned long size) +{ + if (__builtin_constant_p(size)) { + if (!size) + return BITS_PER_LONG - PAGE_SHIFT; + + if (size < (1UL << PAGE_SHIFT)) + return 0; + + return ilog2((size) - 1) - PAGE_SHIFT + 1; + } + + size--; + size >>= PAGE_SHIFT; +#if BITS_PER_LONG == 32 + return fls(size); +#else + return fls64(size); +#endif +} + +#endif /* __ASSEMBLER__ */ + +#endif /* __ASM_GENERIC_GETORDER_H */ -- cgit v1.3.1