summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--arch/arm64/include/asm/fixmap.h4
-rw-r--r--arch/arm64/kernel/entry.S53
-rw-r--r--arch/arm64/kernel/vmlinux.lds.S3
-rw-r--r--arch/arm64/mm/mmu.c10
4 files changed, 30 insertions, 40 deletions
diff --git a/arch/arm64/include/asm/fixmap.h b/arch/arm64/include/asm/fixmap.h
index daff882883f9..71ed5fdf718b 100644
--- a/arch/arm64/include/asm/fixmap.h
+++ b/arch/arm64/include/asm/fixmap.h
@@ -62,10 +62,12 @@ enum fixed_addresses {
#endif /* CONFIG_ACPI_APEI_GHES */
#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+#ifdef CONFIG_RELOCATABLE
+ FIX_ENTRY_TRAMP_TEXT4, /* one extra slot for the data page */
+#endif
FIX_ENTRY_TRAMP_TEXT3,
FIX_ENTRY_TRAMP_TEXT2,
FIX_ENTRY_TRAMP_TEXT1,
- FIX_ENTRY_TRAMP_DATA,
#define TRAMP_VALIAS (__fix_to_virt(FIX_ENTRY_TRAMP_TEXT1))
#endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
__end_of_permanent_fixed_addresses,
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 5b82b9292400..254fe31c03a0 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -636,18 +636,28 @@ alternative_else_nop_endif
*/
.endm
- .macro tramp_data_page dst
- adr_l \dst, .entry.tramp.text
- sub \dst, \dst, PAGE_SIZE
- .endm
-
- .macro tramp_data_read_var dst, var
-#ifdef CONFIG_RANDOMIZE_BASE
- tramp_data_page \dst
- add \dst, \dst, #:lo12:__entry_tramp_data_\var
- ldr \dst, [\dst]
+ .macro tramp_data_read_var dst, var
+#ifdef CONFIG_RELOCATABLE
+ ldr \dst, .L__tramp_data_\var
+ .ifndef .L__tramp_data_\var
+ .pushsection ".entry.tramp.rodata", "a", %progbits
+ .align 3
+.L__tramp_data_\var:
+ .quad \var
+ .popsection
+ .endif
#else
- ldr \dst, =\var
+ /*
+ * As !RELOCATABLE implies !RANDOMIZE_BASE the address is always a
+ * compile time constant (and hence not secret and not worth hiding).
+ *
+ * As statically allocated kernel code and data always live in the top
+ * 47 bits of the address space we can sign-extend bit 47 and avoid an
+ * instruction to load the upper 16 bits (which must be 0xFFFF).
+ */
+ movz \dst, :abs_g2_s:\var
+ movk \dst, :abs_g1_nc:\var
+ movk \dst, :abs_g0_nc:\var
#endif
.endm
@@ -695,7 +705,7 @@ alternative_else_nop_endif
msr vbar_el1, x30
isb
.else
- ldr x30, =vectors
+ adr_l x30, vectors
.endif // \kpti == 1
.if \bhb == BHB_MITIGATION_FW
@@ -764,24 +774,7 @@ SYM_CODE_END(tramp_exit_native)
SYM_CODE_START(tramp_exit_compat)
tramp_exit 32
SYM_CODE_END(tramp_exit_compat)
-
- .ltorg
.popsection // .entry.tramp.text
-#ifdef CONFIG_RANDOMIZE_BASE
- .pushsection ".rodata", "a"
- .align PAGE_SHIFT
-SYM_DATA_START(__entry_tramp_data_start)
-__entry_tramp_data_vectors:
- .quad vectors
-#ifdef CONFIG_ARM_SDE_INTERFACE
-__entry_tramp_data___sdei_asm_handler:
- .quad __sdei_asm_handler
-#endif /* CONFIG_ARM_SDE_INTERFACE */
-__entry_tramp_data_this_cpu_vector:
- .quad this_cpu_vector
-SYM_DATA_END(__entry_tramp_data_start)
- .popsection // .rodata
-#endif /* CONFIG_RANDOMIZE_BASE */
#endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
/*
@@ -932,7 +925,6 @@ NOKPROBE(call_on_irq_stack)
* This clobbers x4, __sdei_handler() will restore this from firmware's
* copy.
*/
-.ltorg
.pushsection ".entry.tramp.text", "ax"
SYM_CODE_START(__sdei_asm_entry_trampoline)
mrs x4, ttbr1_el1
@@ -967,7 +959,6 @@ SYM_CODE_START(__sdei_asm_exit_trampoline)
1: sdei_handler_exit exit_mode=x2
SYM_CODE_END(__sdei_asm_exit_trampoline)
NOKPROBE(__sdei_asm_exit_trampoline)
- .ltorg
.popsection // .entry.tramp.text
#endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index 2d4a8f995175..8a078c0ee140 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -115,7 +115,8 @@ jiffies = jiffies_64;
__entry_tramp_text_start = .; \
*(.entry.tramp.text) \
. = ALIGN(PAGE_SIZE); \
- __entry_tramp_text_end = .;
+ __entry_tramp_text_end = .; \
+ *(.entry.tramp.rodata)
#else
#define TRAMP_TEXT
#endif
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 5e2feb0c442d..c5563ff990da 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -672,13 +672,9 @@ static int __init map_entry_trampoline(void)
__set_fixmap(FIX_ENTRY_TRAMP_TEXT1 - i,
pa_start + i * PAGE_SIZE, prot);
- if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
- extern char __entry_tramp_data_start[];
-
- __set_fixmap(FIX_ENTRY_TRAMP_DATA,
- __pa_symbol(__entry_tramp_data_start),
- PAGE_KERNEL_RO);
- }
+ if (IS_ENABLED(CONFIG_RELOCATABLE))
+ __set_fixmap(FIX_ENTRY_TRAMP_TEXT1 - i,
+ pa_start + i * PAGE_SIZE, PAGE_KERNEL_RO);
return 0;
}