lkml.org 
[lkml]   [2018]   [Jul]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v11 12/15] arm64: kexec_file: invoke the kernel without purgatory
Date
On arm64, purgatory would do almost nothing. So just invoke secondary
kernel directly by jumping into its entry code.

While, in this case, cpu_soft_restart() must be called with dtb address
in the fifth argument, the behavior still stays compatible with kexec_load
case as long as the argument is null.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
---
arch/arm64/kernel/cpu-reset.S | 8 ++++----
arch/arm64/kernel/machine_kexec.c | 12 ++++++++++--
arch/arm64/kernel/relocate_kernel.S | 3 ++-
3 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/kernel/cpu-reset.S b/arch/arm64/kernel/cpu-reset.S
index 8021b46c9743..a2be30275a73 100644
--- a/arch/arm64/kernel/cpu-reset.S
+++ b/arch/arm64/kernel/cpu-reset.S
@@ -22,11 +22,11 @@
* __cpu_soft_restart(el2_switch, entry, arg0, arg1, arg2) - Helper for
* cpu_soft_restart.
*
- * @el2_switch: Flag to indicate a swich to EL2 is needed.
+ * @el2_switch: Flag to indicate a switch to EL2 is needed.
* @entry: Location to jump to for soft reset.
- * arg0: First argument passed to @entry.
- * arg1: Second argument passed to @entry.
- * arg2: Third argument passed to @entry.
+ * arg0: First argument passed to @entry. (relocation list)
+ * arg1: Second argument passed to @entry.(physical kernel entry)
+ * arg2: Third argument passed to @entry. (physical dtb address)
*
* Put the CPU into the same state as it would be if it had been reset, and
* branch to what would be the reset vector. It must be executed with the
diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c
index f76ea92dff91..830a5063e09d 100644
--- a/arch/arm64/kernel/machine_kexec.c
+++ b/arch/arm64/kernel/machine_kexec.c
@@ -205,10 +205,18 @@ void machine_kexec(struct kimage *kimage)
* uses physical addressing to relocate the new image to its final
* position and transfers control to the image entry point when the
* relocation is complete.
+ * In kexec case, kimage->start points to purgatory assuming that
+ * kernel entry and dtb address are embedded in purgatory by
+ * userspace (kexec-tools).
+ * In kexec_file case, the kernel starts directly without purgatory.
*/
-
cpu_soft_restart(kimage != kexec_crash_image,
- reboot_code_buffer_phys, kimage->head, kimage->start, 0);
+ reboot_code_buffer_phys, kimage->head, kimage->start,
+#ifdef CONFIG_KEXEC_FILE
+ kimage->arch.dtb_mem);
+#else
+ 0);
+#endif

BUG(); /* Should never get here. */
}
diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S
index f407e422a720..95fd94209aae 100644
--- a/arch/arm64/kernel/relocate_kernel.S
+++ b/arch/arm64/kernel/relocate_kernel.S
@@ -32,6 +32,7 @@
ENTRY(arm64_relocate_new_kernel)

/* Setup the list loop variables. */
+ mov x18, x2 /* x18 = dtb address */
mov x17, x1 /* x17 = kimage_start */
mov x16, x0 /* x16 = kimage_head */
raw_dcache_line_size x15, x0 /* x15 = dcache line size */
@@ -107,7 +108,7 @@ ENTRY(arm64_relocate_new_kernel)
isb

/* Start new image. */
- mov x0, xzr
+ mov x0, x18
mov x1, xzr
mov x2, xzr
mov x3, xzr
--
2.17.0
\
 
 \ /
  Last update: 2018-07-11 09:43    [W:0.107 / U:0.964 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site