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Message-Id: <20210527150526.271941-6-pasha.tatashin@soleen.com>
Date: Thu, 27 May 2021 11:05:13 -0400
From: Pavel Tatashin <pasha.tatashin@...een.com>
To: pasha.tatashin@...een.com, jmorris@...ei.org, sashal@...nel.org,
ebiederm@...ssion.com, kexec@...ts.infradead.org,
linux-kernel@...r.kernel.org, corbet@....net,
catalin.marinas@....com, will@...nel.org,
linux-arm-kernel@...ts.infradead.org, maz@...nel.org,
james.morse@....com, vladimir.murzin@....com,
matthias.bgg@...il.com, linux-mm@...ck.org, mark.rutland@....com,
steve.capper@....com, rfontana@...hat.com, tglx@...utronix.de,
selindag@...il.com, tyhicks@...ux.microsoft.com,
kernelfans@...il.com, akpm@...ux-foundation.org,
madvenka@...ux.microsoft.com
Subject: [PATCH 05/18] 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.
Suggested-by: James Morse <james.morse@....com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@...een.com>
---
arch/arm64/include/asm/trans_pgd.h | 3 +++
arch/arm64/include/asm/virt.h | 3 +++
arch/arm64/kernel/hibernate.c | 28 ++++++++++------------------
arch/arm64/mm/trans_pgd.c | 20 ++++++++++++++++++++
4 files changed, 36 insertions(+), 18 deletions(-)
diff --git a/arch/arm64/include/asm/trans_pgd.h b/arch/arm64/include/asm/trans_pgd.h
index 5d08e5adf3d5..e0760e52d36d 100644
--- a/arch/arm64/include/asm/trans_pgd.h
+++ b/arch/arm64/include/asm/trans_pgd.h
@@ -36,4 +36,7 @@ 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);
+
#endif /* _ASM_TRANS_TABLE_H */
diff --git a/arch/arm64/include/asm/virt.h b/arch/arm64/include/asm/virt.h
index 4216c8623538..bfbb66018114 100644
--- a/arch/arm64/include/asm/virt.h
+++ b/arch/arm64/include/asm/virt.h
@@ -67,6 +67,9 @@
*/
extern u32 __boot_cpu_mode[2];
+extern char __hyp_stub_vectors[];
+#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.c b/arch/arm64/kernel/hibernate.c
index c764574a1acb..0b8bad8bb6eb 100644
--- a/arch/arm64/kernel/hibernate.c
+++ b/arch/arm64/kernel/hibernate.c
@@ -48,12 +48,6 @@
*/
extern int in_suspend;
-/* 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[];
-
/*
* The logical cpu number we should resume on, initialised to a non-cpu
* number.
@@ -428,6 +422,7 @@ 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 = {
@@ -455,6 +450,14 @@ int swsusp_arch_resume(void)
return -ENOMEM;
}
+ if (is_hyp_callable()) {
+ 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
@@ -467,25 +470,14 @@ int swsusp_arch_resume(void)
return rc;
}
- /*
- * 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.
- */
- __flush_dcache_area(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 (is_hyp_callable()) {
- phys_addr_t el2_vectors = (phys_addr_t)hibernate_exit;
- el2_vectors += hibernate_el2_vectors -
- __hibernate_exit_text_start; /* offset */
-
+ if (is_hyp_callable())
__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/trans_pgd.c b/arch/arm64/mm/trans_pgd.c
index 527f0a39c3da..61549451ed3a 100644
--- a/arch/arm64/mm/trans_pgd.c
+++ b/arch/arm64/mm/trans_pgd.c
@@ -322,3 +322,23 @@ 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, &__hyp_stub_vectors, ARM64_VECTOR_TABLE_LEN);
+ __flush_icache_range((unsigned long)hyp_stub,
+ (unsigned long)hyp_stub + ARM64_VECTOR_TABLE_LEN);
+ __flush_dcache_area(hyp_stub, ARM64_VECTOR_TABLE_LEN);
+
+ return 0;
+}
--
2.25.1
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