On Wed, 6 Mar 2024 at 09:56, Yunhui Cui <cuiyunhui@xxxxxxxxxxxxx> wrote: > > Compared with gcc version 12, gcc version 13 uses the gp > register for compilation optimization, but the efistub module > does not initialize gp. > > Signed-off-by: Yunhui Cui <cuiyunhui@xxxxxxxxxxxxx> > Co-Developed-by: Zhipeng Xu <xuzhipeng.1973@xxxxxxxxxxxxx> This needs a sign-off, and your signoff needs to come after. > --- > arch/riscv/kernel/efi-header.S | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/arch/riscv/kernel/efi-header.S b/arch/riscv/kernel/efi-header.S > index 515b2dfbca75..fa17c08c092a 100644 > --- a/arch/riscv/kernel/efi-header.S > +++ b/arch/riscv/kernel/efi-header.S > @@ -40,7 +40,7 @@ optional_header: > .long __pecoff_data_virt_end - __pecoff_text_end // SizeOfInitializedData > #endif > .long 0 // SizeOfUninitializedData > - .long __efistub_efi_pe_entry - _start // AddressOfEntryPoint > + .long _efistub_entry - _start // AddressOfEntryPoint > .long efi_header_end - _start // BaseOfCode > #ifdef CONFIG_32BIT > .long __pecoff_text_end - _start // BaseOfData > @@ -121,4 +121,13 @@ section_table: > > .balign 0x1000 > efi_header_end: > + > + .global _efistub_entry > +_efistub_entry: This should go into .text or .init.text, not the header. > + /* Reload the global pointer */ > + load_global_pointer > + What is supposed to happen here if CONFIG_SHADOW_CALL_STACK=y? The EFI stub Makefile removes the SCS CFLAGS, so the stub will be built without shadow call stack support, which I guess means that it might use GP as a global pointer as usual? > + call __efistub_efi_pe_entry > + ret > + You are returning to the firmware here, but after modifying the GP register. Shouldn't you restore it to its old value?
