diff options
Diffstat (limited to 'arch/arm64/kernel/efi-entry.S')
| -rw-r--r-- | arch/arm64/kernel/efi-entry.S | 27 |
1 files changed, 21 insertions, 6 deletions
diff --git a/arch/arm64/kernel/efi-entry.S b/arch/arm64/kernel/efi-entry.S index 619b1dd7bcde..d18a44940968 100644 --- a/arch/arm64/kernel/efi-entry.S +++ b/arch/arm64/kernel/efi-entry.S @@ -54,18 +54,17 @@ ENTRY(efi_stub_entry) b.eq efi_load_fail /* - * efi_entry() will have relocated the kernel image if necessary - * and we return here with device tree address in x0 and the kernel - * entry point stored at *image_addr. Save those values in registers - * which are callee preserved. + * efi_entry() will have copied the kernel image if necessary and we + * return here with device tree address in x0 and the kernel entry + * point stored at *image_addr. Save those values in registers which + * are callee preserved. */ mov x20, x0 // DTB address ldr x0, [sp, #16] // relocated _text address mov x21, x0 /* - * Flush dcache covering current runtime addresses - * of kernel text/data. Then flush all of icache. + * Calculate size of the kernel Image (same for original and copy). */ adrp x1, _text add x1, x1, #:lo12:_text @@ -73,9 +72,24 @@ ENTRY(efi_stub_entry) add x2, x2, #:lo12:_edata sub x1, x2, x1 + /* + * Flush the copied Image to the PoC, and ensure it is not shadowed by + * stale icache entries from before relocation. + */ bl __flush_dcache_area ic ialluis + /* + * Ensure that the rest of this function (in the original Image) is + * visible when the caches are disabled. The I-cache can't have stale + * entries for the VA range of the current image, so no maintenance is + * necessary. + */ + adr x0, efi_stub_entry + adr x1, efi_stub_entry_end + sub x1, x1, x0 + bl __flush_dcache_area + /* Turn off Dcache and MMU */ mrs x0, CurrentEL cmp x0, #CurrentEL_EL2 @@ -105,4 +119,5 @@ efi_load_fail: ldp x29, x30, [sp], #32 ret +efi_stub_entry_end: ENDPROC(efi_stub_entry) |