Kernel/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-01-08 14:23:19 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

powerpc/optprobes: Add register argument to patch_imm64_load_insns()

Browse Source 
Currently patch_imm32_load_insns() is used to load an instruction to
r4 to be emulated by emulate_step(). For prefixed instructions we
would like to be able to load a 64bit immediate to r4. To prepare for
this make patch_imm64_load_insns() take an argument that decides which
register to load an immediate to - rather than hardcoding r3.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200516115449.4168796-1-mpe@ellerman.id.au
This commit is contained in:
Jordan Niethe 2020-05-15 11:15:28 +10:00 committed by Michael Ellerman
parent b691505ef9
commit 7a8818e0df
1 changed files with 17 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
arch/powerpc/kernel/optprobes.c
View File

@ -162,38 +162,38 @@ void patch_imm32_load_insns(unsigned int val, kprobe_opcode_t *addr)
/*
* Generate instructions to load provided immediate 64-bit value
* to register 'r3' and patch these instructions at 'addr'.
* to register 'reg' and patch these instructions at 'addr'.
*/
void patch_imm64_load_insns(unsigned long val, kprobe_opcode_t *addr)
void patch_imm64_load_insns(unsigned long val, int reg, kprobe_opcode_t *addr)
{
/* lis r3,(op)@highest */
/* lis reg,(op)@highest */
patch_instruction((struct ppc_inst *)addr,
ppc_inst(PPC_INST_ADDIS | ___PPC_RT(3) |
ppc_inst(PPC_INST_ADDIS | ___PPC_RT(reg) |
((val >> 48) & 0xffff)));
addr++;
/* ori r3,r3,(op)@higher */
/* ori reg,reg,(op)@higher */
patch_instruction((struct ppc_inst *)addr,
ppc_inst(PPC_INST_ORI | ___PPC_RA(3) |
___PPC_RS(3) | ((val >> 32) & 0xffff)));
ppc_inst(PPC_INST_ORI | ___PPC_RA(reg) |
___PPC_RS(reg) | ((val >> 32) & 0xffff)));
addr++;
/* rldicr r3,r3,32,31 */
/* rldicr reg,reg,32,31 */
patch_instruction((struct ppc_inst *)addr,
ppc_inst(PPC_INST_RLDICR | ___PPC_RA(3) |
___PPC_RS(3) | __PPC_SH64(32) | __PPC_ME64(31)));
ppc_inst(PPC_INST_RLDICR | ___PPC_RA(reg) |
___PPC_RS(reg) | __PPC_SH64(32) | __PPC_ME64(31)));
addr++;
/* oris r3,r3,(op)@h */
/* oris reg,reg,(op)@h */
patch_instruction((struct ppc_inst *)addr,
ppc_inst(PPC_INST_ORIS | ___PPC_RA(3) |
___PPC_RS(3) | ((val >> 16) & 0xffff)));
ppc_inst(PPC_INST_ORIS | ___PPC_RA(reg) |
___PPC_RS(reg) | ((val >> 16) & 0xffff)));
addr++;
/* ori r3,r3,(op)@l */
/* ori reg,reg,(op)@l */
patch_instruction((struct ppc_inst *)addr,
ppc_inst(PPC_INST_ORI | ___PPC_RA(3) |
___PPC_RS(3) | (val & 0xffff)));
ppc_inst(PPC_INST_ORI | ___PPC_RA(reg) |
___PPC_RS(reg) | (val & 0xffff)));
}
int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
@ -249,7 +249,7 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
* Fixup the template with instructions to:
* 1. load the address of the actual probepoint
*/
patch_imm64_load_insns((unsigned long)op, buff + TMPL_OP_IDX);
patch_imm64_load_insns((unsigned long)op, 3, buff + TMPL_OP_IDX);
/*
* 2. branch to optimized_callback() and emulate_step()