Hi Sergei,
On 03/12/15 14:24, Sergei Shtylyov wrote:
Hello.
On 12/3/2015 1:08 PM, Matt Redfearn wrote:
If CONFIG_RELOCATABLE is enabled, jump to relocate_kernel.
This function will return the entry point of the relocated kernel if
copy/relocate is sucessful or the original entry point if not. The stack
pointer must then be pointed into the new image.
Signed-off-by: Matt Redfearn <matt.redfearn@xxxxxxxxxx>
---
arch/mips/kernel/head.S | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/arch/mips/kernel/head.S b/arch/mips/kernel/head.S
index 4e4cc5b9a771..7dc043349d66 100644
--- a/arch/mips/kernel/head.S
+++ b/arch/mips/kernel/head.S
@@ -132,7 +132,27 @@ not_found:
set_saved_sp sp, t0, t1
PTR_SUBU sp, 4 * SZREG # init stack pointer
+#ifdef CONFIG_RELOCATABLE
+ /* Copy kernel and apply the relocations */
+ jal relocate_kernel
+
+ /* Repoint the sp into the new kernel image */
+ PTR_LI sp, _THREAD_SIZE - 32 - PT_SIZE
+ PTR_ADDU sp, $28
Can't you account for it in the previous PTR_LI?
During relocate_kernel, $28, pointer to the current thread, has been
moved by an unknown (here) number of bytes to point to the
init_thread_union within the new kernel. The stack pointer must now be
pointed there too. Since we don't know the offset from the original
kernel it's easier to simply recalculate it.
Thanks,
Matt
+ set_saved_sp sp, t0, t1
+ PTR_SUBU sp, 4 * SZREG # init stack pointer
[...]
MBR, Sergei
