From 788bfdd97434982b6d575062581e8e72eea755af Mon Sep 17 00:00:00 2001 From: Pasha Tatashin Date: Thu, 30 Sep 2021 14:31:00 +0000 Subject: [PATCH] arm64: trans_pgd: hibernate: Add trans_pgd_copy_el2_vectors Users of trans_pgd may also need a copy of vector table because it is also may be overwritten if a linear map can be overwritten. Move setup of EL2 vectors from hibernate to trans_pgd, so it can be later shared with kexec as well. Signed-off-by: Pasha Tatashin Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/20210930143113.1502553-3-pasha.tatashin@soleen.com Signed-off-by: Will Deacon --- arch/arm64/include/asm/trans_pgd.h | 9 ++++-- arch/arm64/include/asm/virt.h | 2 ++ arch/arm64/kernel/hibernate-asm.S | 52 ---------------------------------- arch/arm64/kernel/hibernate.c | 26 +++++++---------- arch/arm64/mm/Makefile | 1 + arch/arm64/mm/trans_pgd-asm.S | 58 ++++++++++++++++++++++++++++++++++++++ arch/arm64/mm/trans_pgd.c | 27 ++++++++++++++++-- 7 files changed, 103 insertions(+), 72 deletions(-) create mode 100644 arch/arm64/mm/trans_pgd-asm.S diff --git a/arch/arm64/include/asm/trans_pgd.h b/arch/arm64/include/asm/trans_pgd.h index 5d08e5a..7b04d32 100644 --- a/arch/arm64/include/asm/trans_pgd.h +++ b/arch/arm64/include/asm/trans_pgd.h @@ -1,8 +1,8 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* - * Copyright (c) 2020, Microsoft Corporation. - * Pavel Tatashin + * Copyright (c) 2021, Microsoft Corporation. + * Pasha Tatashin */ #ifndef _ASM_TRANS_TABLE_H @@ -36,4 +36,9 @@ int trans_pgd_map_page(struct trans_pgd_info *info, pgd_t *trans_pgd, int trans_pgd_idmap_page(struct trans_pgd_info *info, phys_addr_t *trans_ttbr0, unsigned long *t0sz, void *page); +int trans_pgd_copy_el2_vectors(struct trans_pgd_info *info, + phys_addr_t *el2_vectors); + +extern char trans_pgd_stub_vectors[]; + #endif /* _ASM_TRANS_TABLE_H */ diff --git a/arch/arm64/include/asm/virt.h b/arch/arm64/include/asm/virt.h index a9457e9..3c8af033 100644 --- a/arch/arm64/include/asm/virt.h +++ b/arch/arm64/include/asm/virt.h @@ -67,6 +67,8 @@ */ extern u32 __boot_cpu_mode[2]; +#define ARM64_VECTOR_TABLE_LEN SZ_2K + void __hyp_set_vectors(phys_addr_t phys_vector_base); void __hyp_reset_vectors(void); diff --git a/arch/arm64/kernel/hibernate-asm.S b/arch/arm64/kernel/hibernate-asm.S index 81c0186..a30a2c3 100644 --- a/arch/arm64/kernel/hibernate-asm.S +++ b/arch/arm64/kernel/hibernate-asm.S @@ -112,56 +112,4 @@ alternative_insn "dc cvau, x4", "dc civac, x4", ARM64_WORKAROUND_CLEAN_CACHE hvc #0 3: ret SYM_CODE_END(swsusp_arch_suspend_exit) - -/* - * Restore the hyp stub. - * This must be done before the hibernate page is unmapped by _cpu_resume(), - * but happens before any of the hyp-stub's code is cleaned to PoC. - * - * x24: The physical address of __hyp_stub_vectors - */ -SYM_CODE_START_LOCAL(el1_sync) - msr vbar_el2, x24 - eret -SYM_CODE_END(el1_sync) - -.macro invalid_vector label -SYM_CODE_START_LOCAL(\label) - b \label -SYM_CODE_END(\label) -.endm - - invalid_vector el2_sync_invalid - invalid_vector el2_irq_invalid - invalid_vector el2_fiq_invalid - invalid_vector el2_error_invalid - invalid_vector el1_sync_invalid - invalid_vector el1_irq_invalid - invalid_vector el1_fiq_invalid - invalid_vector el1_error_invalid - -/* el2 vectors - switch el2 here while we restore the memory image. */ - .align 11 -SYM_CODE_START(hibernate_el2_vectors) - ventry el2_sync_invalid // Synchronous EL2t - ventry el2_irq_invalid // IRQ EL2t - ventry el2_fiq_invalid // FIQ EL2t - ventry el2_error_invalid // Error EL2t - - ventry el2_sync_invalid // Synchronous EL2h - ventry el2_irq_invalid // IRQ EL2h - ventry el2_fiq_invalid // FIQ EL2h - ventry el2_error_invalid // Error EL2h - - ventry el1_sync // Synchronous 64-bit EL1 - ventry el1_irq_invalid // IRQ 64-bit EL1 - ventry el1_fiq_invalid // FIQ 64-bit EL1 - ventry el1_error_invalid // Error 64-bit EL1 - - ventry el1_sync_invalid // Synchronous 32-bit EL1 - ventry el1_irq_invalid // IRQ 32-bit EL1 - ventry el1_fiq_invalid // FIQ 32-bit EL1 - ventry el1_error_invalid // Error 32-bit EL1 -SYM_CODE_END(hibernate_el2_vectors) - .popsection diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c index 4c9533f..b96ef90 100644 --- a/arch/arm64/kernel/hibernate.c +++ b/arch/arm64/kernel/hibernate.c @@ -51,9 +51,6 @@ extern int in_suspend; /* Do we need to reset el2? */ #define el2_reset_needed() (is_hyp_nvhe()) -/* temporary el2 vectors in the __hibernate_exit_text section. */ -extern char hibernate_el2_vectors[]; - /* hyp-stub vectors, used to restore el2 during resume from hibernate. */ extern char __hyp_stub_vectors[]; @@ -434,6 +431,7 @@ int swsusp_arch_resume(void) void *zero_page; size_t exit_size; pgd_t *tmp_pg_dir; + phys_addr_t el2_vectors; void __noreturn (*hibernate_exit)(phys_addr_t, phys_addr_t, void *, void *, phys_addr_t, phys_addr_t); struct trans_pgd_info trans_info = { @@ -461,6 +459,14 @@ int swsusp_arch_resume(void) return -ENOMEM; } + if (el2_reset_needed()) { + rc = trans_pgd_copy_el2_vectors(&trans_info, &el2_vectors); + if (rc) { + pr_err("Failed to setup el2 vectors\n"); + return rc; + } + } + exit_size = __hibernate_exit_text_end - __hibernate_exit_text_start; /* * Copy swsusp_arch_suspend_exit() to a safe page. This will generate @@ -474,25 +480,13 @@ int swsusp_arch_resume(void) } /* - * The hibernate exit text contains a set of el2 vectors, that will - * be executed at el2 with the mmu off in order to reload hyp-stub. - */ - dcache_clean_inval_poc((unsigned long)hibernate_exit, - (unsigned long)hibernate_exit + exit_size); - - /* * KASLR will cause the el2 vectors to be in a different location in * the resumed kernel. Load hibernate's temporary copy into el2. * * We can skip this step if we booted at EL1, or are running with VHE. */ - if (el2_reset_needed()) { - phys_addr_t el2_vectors = (phys_addr_t)hibernate_exit; - el2_vectors += hibernate_el2_vectors - - __hibernate_exit_text_start; /* offset */ - + if (el2_reset_needed()) __hyp_set_vectors(el2_vectors); - } hibernate_exit(virt_to_phys(tmp_pg_dir), resume_hdr.ttbr1_el1, resume_hdr.reenter_kernel, restore_pblist, diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile index f188c90..ff1e800 100644 --- a/arch/arm64/mm/Makefile +++ b/arch/arm64/mm/Makefile @@ -7,6 +7,7 @@ obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o obj-$(CONFIG_PTDUMP_CORE) += ptdump.o obj-$(CONFIG_PTDUMP_DEBUGFS) += ptdump_debugfs.o obj-$(CONFIG_TRANS_TABLE) += trans_pgd.o +obj-$(CONFIG_TRANS_TABLE) += trans_pgd-asm.o obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o obj-$(CONFIG_ARM64_MTE) += mteswap.o KASAN_SANITIZE_physaddr.o += n diff --git a/arch/arm64/mm/trans_pgd-asm.S b/arch/arm64/mm/trans_pgd-asm.S new file mode 100644 index 0000000..8c4bffe --- /dev/null +++ b/arch/arm64/mm/trans_pgd-asm.S @@ -0,0 +1,58 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +/* + * Copyright (c) 2021, Microsoft Corporation. + * Pasha Tatashin + */ + +#include +#include +#include + +.macro invalid_vector label +SYM_CODE_START_LOCAL(\label) + .align 7 + b \label +SYM_CODE_END(\label) +.endm + +.macro el1_sync_vector +SYM_CODE_START_LOCAL(el1_sync) + .align 7 + cmp x0, #HVC_SET_VECTORS /* Called from hibernate */ + b.ne 1f + msr vbar_el2, x1 + mov x0, xzr + eret +1: /* Unexpected argument, set an error */ + mov_q x0, HVC_STUB_ERR + eret +SYM_CODE_END(el1_sync) +.endm + +SYM_CODE_START(trans_pgd_stub_vectors) + invalid_vector hyp_stub_el2t_sync_invalid // Synchronous EL2t + invalid_vector hyp_stub_el2t_irq_invalid // IRQ EL2t + invalid_vector hyp_stub_el2t_fiq_invalid // FIQ EL2t + invalid_vector hyp_stub_el2t_error_invalid // Error EL2t + + invalid_vector hyp_stub_el2h_sync_invalid // Synchronous EL2h + invalid_vector hyp_stub_el2h_irq_invalid // IRQ EL2h + invalid_vector hyp_stub_el2h_fiq_invalid // FIQ EL2h + invalid_vector hyp_stub_el2h_error_invalid // Error EL2h + + el1_sync_vector // Synchronous 64-bit EL1 + invalid_vector hyp_stub_el1_irq_invalid // IRQ 64-bit EL1 + invalid_vector hyp_stub_el1_fiq_invalid // FIQ 64-bit EL1 + invalid_vector hyp_stub_el1_error_invalid // Error 64-bit EL1 + + invalid_vector hyp_stub_32b_el1_sync_invalid // Synchronous 32-bit EL1 + invalid_vector hyp_stub_32b_el1_irq_invalid // IRQ 32-bit EL1 + invalid_vector hyp_stub_32b_el1_fiq_invalid // FIQ 32-bit EL1 + invalid_vector hyp_stub_32b_el1_error_invalid // Error 32-bit EL1 + .align 11 +SYM_INNER_LABEL(__trans_pgd_stub_vectors_end, SYM_L_LOCAL) +SYM_CODE_END(trans_pgd_stub_vectors) + +# Check the trans_pgd_stub_vectors didn't overflow +.org . - (__trans_pgd_stub_vectors_end - trans_pgd_stub_vectors) + SZ_2K diff --git a/arch/arm64/mm/trans_pgd.c b/arch/arm64/mm/trans_pgd.c index 527f0a3..26bd8f2 100644 --- a/arch/arm64/mm/trans_pgd.c +++ b/arch/arm64/mm/trans_pgd.c @@ -5,8 +5,8 @@ * * This file derived from: arch/arm64/kernel/hibernate.c * - * Copyright (c) 2020, Microsoft Corporation. - * Pavel Tatashin + * Copyright (c) 2021, Microsoft Corporation. + * Pasha Tatashin * */ @@ -322,3 +322,26 @@ int trans_pgd_idmap_page(struct trans_pgd_info *info, phys_addr_t *trans_ttbr0, return 0; } + +/* + * Create a copy of the vector table so we can call HVC_SET_VECTORS or + * HVC_SOFT_RESTART from contexts where the table may be overwritten. + */ +int trans_pgd_copy_el2_vectors(struct trans_pgd_info *info, + phys_addr_t *el2_vectors) +{ + void *hyp_stub = trans_alloc(info); + + if (!hyp_stub) + return -ENOMEM; + *el2_vectors = virt_to_phys(hyp_stub); + memcpy(hyp_stub, &trans_pgd_stub_vectors, ARM64_VECTOR_TABLE_LEN); + caches_clean_inval_pou((unsigned long)hyp_stub, + (unsigned long)hyp_stub + + ARM64_VECTOR_TABLE_LEN); + dcache_clean_inval_poc((unsigned long)hyp_stub, + (unsigned long)hyp_stub + + ARM64_VECTOR_TABLE_LEN); + + return 0; +} -- 2.7.4