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/xen/page.h | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 include/xen/page.h (limited to 'include/xen/page.h') diff --git a/include/xen/page.h b/include/xen/page.h new file mode 100644 index 000000000..285677b42 --- /dev/null +++ b/include/xen/page.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _XEN_PAGE_H +#define _XEN_PAGE_H + +#include + +/* The hypercall interface supports only 4KB page */ +#define XEN_PAGE_SHIFT 12 +#define XEN_PAGE_SIZE (_AC(1, UL) << XEN_PAGE_SHIFT) +#define XEN_PAGE_MASK (~(XEN_PAGE_SIZE-1)) +#define xen_offset_in_page(p) ((unsigned long)(p) & ~XEN_PAGE_MASK) + +/* + * We assume that PAGE_SIZE is a multiple of XEN_PAGE_SIZE + * XXX: Add a BUILD_BUG_ON? + */ + +#define xen_pfn_to_page(xen_pfn) \ + (pfn_to_page((unsigned long)(xen_pfn) >> (PAGE_SHIFT - XEN_PAGE_SHIFT))) +#define page_to_xen_pfn(page) \ + ((page_to_pfn(page)) << (PAGE_SHIFT - XEN_PAGE_SHIFT)) + +#define XEN_PFN_PER_PAGE (PAGE_SIZE / XEN_PAGE_SIZE) + +#define XEN_PFN_DOWN(x) ((x) >> XEN_PAGE_SHIFT) +#define XEN_PFN_UP(x) (((x) + XEN_PAGE_SIZE-1) >> XEN_PAGE_SHIFT) + +#include + +/* Return the GFN associated to the first 4KB of the page */ +static inline unsigned long xen_page_to_gfn(struct page *page) +{ + return pfn_to_gfn(page_to_xen_pfn(page)); +} + +struct xen_memory_region { + unsigned long start_pfn; + unsigned long n_pfns; +}; + +#define XEN_EXTRA_MEM_MAX_REGIONS 128 /* == E820_MAX_ENTRIES_ZEROPAGE */ + +extern __initdata +struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS]; + +extern unsigned long xen_released_pages; + +#endif /* _XEN_PAGE_H */ -- cgit v1.3.1