@@ -987,7 +987,7 @@ __ni_sys_trace:
.macro tramp_map_kernel, tmp
mrs \tmp, ttbr1_el1
- sub \tmp, \tmp, #(SWAPPER_DIR_SIZE + RESERVED_TTBR0_SIZE)
+ add \tmp, \tmp, #(PAGE_SIZE + RESERVED_TTBR0_SIZE)
bic \tmp, \tmp, #USER_ASID_FLAG
msr ttbr1_el1, \tmp
#ifdef CONFIG_QCOM_FALKOR_ERRATUM_1003
@@ -1006,7 +1006,7 @@ alternative_else_nop_endif
.macro tramp_unmap_kernel, tmp
mrs \tmp, ttbr1_el1
- add \tmp, \tmp, #(SWAPPER_DIR_SIZE + RESERVED_TTBR0_SIZE)
+ sub \tmp, \tmp, #(PAGE_SIZE + RESERVED_TTBR0_SIZE)
orr \tmp, \tmp, #USER_ASID_FLAG
msr ttbr1_el1, \tmp
/*
@@ -218,6 +218,12 @@ SECTIONS
. = ALIGN(PAGE_SIZE);
idmap_pg_dir = .;
. += IDMAP_DIR_SIZE;
+
+#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+ tramp_pg_dir = .;
+ . += PAGE_SIZE;
+#endif
+
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
reserved_ttbr0 = .;
. += RESERVED_TTBR0_SIZE;
@@ -225,11 +231,6 @@ SECTIONS
swapper_pg_dir = .;
. += SWAPPER_DIR_SIZE;
-#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
- tramp_pg_dir = .;
- . += PAGE_SIZE;
-#endif
-
__pecoff_data_size = ABSOLUTE(. - __initdata_begin);
_end = .;
The trampline page tables are positioned after the early page tables in the kernel linker script. As we are about to change the early page table logic to resolve the swapper size at link time as opposed to compile time, the SWAPPER_DIR_SIZE variable (currently used to locate the trampline) will be rendered unsuitable for low level assembler. This patch solves this issue by moving the trampoline before the PAN page tables. The offset to the trampoline from ttbr1 can then be expressed by: PAGE_SIZE + RESERVED_TTBR0_SIZE, which is available to the entry assembler. Signed-off-by: Steve Capper <steve.capper@arm.com> --- Patch added in V3 of the series to allow it to work with kpti. --- arch/arm64/kernel/entry.S | 4 ++-- arch/arm64/kernel/vmlinux.lds.S | 11 ++++++----- 2 files changed, 8 insertions(+), 7 deletions(-)