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| author |   Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> | 2018-06-07 15:22:02 +0530 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2018-10-20 13:26:43 +1100 |
| commit | 7cd01b08d35f1b7d55686ed8cd57c94d3406ec8f (patch) | |
| tree | ba2112d797cf4e9ba7c690fe9bbe07dad8d5a873 /arch/powerpc/include/asm | |
| parent | powerpc/time: Fix clockevent_decrementer initalisation for PR KVM (diff) | |
| download | linux-dev-7cd01b08d35f1b7d55686ed8cd57c94d3406ec8f.tar.xz linux-dev-7cd01b08d35f1b7d55686ed8cd57c94d3406ec8f.zip | |
powerpc: Add support for function error injection
We implement regs_set_return_value() and override_function_with_return()
for this purpose.
On powerpc, a return from a function (blr) just branches to the location
contained in the link register. So, we can just update pt_regs rather
than redirecting execution to a dummy function that returns.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/include/asm')
| -rw-r--r-- | arch/powerpc/include/asm/error-injection.h | 13 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/ptrace.h | 5 |
2 files changed, 18 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/error-injection.h b/arch/powerpc/include/asm/error-injection.h new file mode 100644 index 000000000000..62fd24739852 --- /dev/null +++ b/arch/powerpc/include/asm/error-injection.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ + +#ifndef _ASM_ERROR_INJECTION_H +#define _ASM_ERROR_INJECTION_H + +#include <linux/compiler.h> +#include <linux/linkage.h> +#include <asm/ptrace.h> +#include <asm-generic/error-injection.h> + +void override_function_with_return(struct pt_regs *regs); + +#endif /* _ASM_ERROR_INJECTION_H */ diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h index 2ba2a1e52291..33196b311964 100644 --- a/arch/powerpc/include/asm/ptrace.h +++ b/arch/powerpc/include/asm/ptrace.h @@ -133,6 +133,11 @@ static inline long regs_return_value(struct pt_regs *regs) return -regs->gpr[3]; } +static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc) +{ + regs->gpr[3] = rc; +} + #ifdef __powerpc64__ #define user_mode(regs) ((((regs)->msr) >> MSR_PR_LG) & 0x1) #else |