diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-10 11:58:20 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-10 11:58:20 -0700 |
commit | e99f23c5bf59219d0cd9b6e0d7d4c1b641a98704 (patch) | |
tree | 89cccd3ab82ef5f2d15f7fdd6f0e5e64a265e56f | |
parent | 23ef827c1bacc6c2b8314ff5bf571d4db57059b0 (diff) | |
parent | 85f58eb1889826b9745737718723a80b639e0fbd (diff) |
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Catalin Marinas:
- Limit the linear region to 51-bit when KVM is running in nVHE mode.
Otherwise, depending on the placement of the ID map, kernel-VA to
hyp-VA translations may produce addresses that either conflict with
other HYP mappings or generate addresses outside of the 52-bit
addressable range.
- Instruct kmemleak not to scan the memory reserved for kdump as this
range is removed from the kernel linear map and therefore not
accessible.
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: kdump: Skip kmemleak scan reserved memory for kdump
arm64: mm: limit linear region to 51 bits for KVM in nVHE mode
-rw-r--r-- | arch/arm64/mm/init.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index b16be52233c6..37a81754d9b6 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -30,6 +30,7 @@ #include <linux/crash_dump.h> #include <linux/hugetlb.h> #include <linux/acpi_iort.h> +#include <linux/kmemleak.h> #include <asm/boot.h> #include <asm/fixmap.h> @@ -101,6 +102,11 @@ static void __init reserve_crashkernel(void) pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n", crash_base, crash_base + crash_size, crash_size >> 20); + /* + * The crashkernel memory will be removed from the kernel linear + * map. Inform kmemleak so that it won't try to access it. + */ + kmemleak_ignore_phys(crash_base); crashk_res.start = crash_base; crashk_res.end = crash_base + crash_size - 1; } @@ -222,7 +228,21 @@ early_param("mem", early_mem); void __init arm64_memblock_init(void) { - const s64 linear_region_size = PAGE_END - _PAGE_OFFSET(vabits_actual); + s64 linear_region_size = PAGE_END - _PAGE_OFFSET(vabits_actual); + + /* + * Corner case: 52-bit VA capable systems running KVM in nVHE mode may + * be limited in their ability to support a linear map that exceeds 51 + * bits of VA space, depending on the placement of the ID map. Given + * that the placement of the ID map may be randomized, let's simply + * limit the kernel's linear map to 51 bits as well if we detect this + * configuration. + */ + if (IS_ENABLED(CONFIG_KVM) && vabits_actual == 52 && + is_hyp_mode_available() && !is_kernel_in_hyp_mode()) { + pr_info("Capping linear region to 51 bits for KVM in nVHE mode on LVA capable hardware.\n"); + linear_region_size = min_t(u64, linear_region_size, BIT(51)); + } /* Remove memory above our supported physical address size */ memblock_remove(1ULL << PHYS_MASK_SHIFT, ULLONG_MAX); |