From: Nicholas Piggin Date: Mon, 26 Sep 2022 05:56:18 +0000 (+1000) Subject: powerpc/64: avoid using r13 in relocate X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=b830c8754e046f96e84da9d3b3e028c4ceef2b18;p=linux.git powerpc/64: avoid using r13 in relocate relocate() uses r13 in early boot before it is used for the paca. Use a different register for this so r13 is kept unchanged until it is set to the paca pointer. Avoid r14 as well while we're here, there's no reason not to use the volatile registers which is a bit less surprising, and r14 could be used as another fixed reg one day. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220926055620.2676869-4-npiggin@gmail.com --- diff --git a/arch/powerpc/kernel/reloc_64.S b/arch/powerpc/kernel/reloc_64.S index 232e4549defe1..efd52f2e70339 100644 --- a/arch/powerpc/kernel/reloc_64.S +++ b/arch/powerpc/kernel/reloc_64.S @@ -27,8 +27,8 @@ _GLOBAL(relocate) add r9,r9,r12 /* r9 has runtime addr of .rela.dyn section */ ld r10,(p_st - 0b)(r12) add r10,r10,r12 /* r10 has runtime addr of _stext */ - ld r13,(p_sym - 0b)(r12) - add r13,r13,r12 /* r13 has runtime addr of .dynsym */ + ld r4,(p_sym - 0b)(r12) + add r4,r4,r12 /* r4 has runtime addr of .dynsym */ /* * Scan the dynamic section for the RELA, RELASZ and RELAENT entries. @@ -84,16 +84,16 @@ _GLOBAL(relocate) ld r0,16(r9) /* reloc->r_addend */ b .Lstore .Luaddr64: - srdi r14,r0,32 /* ELF64_R_SYM(reloc->r_info) */ + srdi r5,r0,32 /* ELF64_R_SYM(reloc->r_info) */ clrldi r0,r0,32 cmpdi r0,R_PPC64_UADDR64 bne .Lnext ld r6,0(r9) ld r0,16(r9) - mulli r14,r14,24 /* 24 == sizeof(elf64_sym) */ - add r14,r14,r13 /* elf64_sym[ELF64_R_SYM] */ - ld r14,8(r14) - add r0,r0,r14 + mulli r5,r5,24 /* 24 == sizeof(elf64_sym) */ + add r5,r5,r4 /* elf64_sym[ELF64_R_SYM] */ + ld r5,8(r5) + add r0,r0,r5 .Lstore: add r0,r0,r3 stdx r0,r7,r6