| Message ID | 20230528000942.231907-1-CFSworks@gmail.com |
|---|---|
| State | Accepted |
| Commit | 8dc2c666808a07c2ad484ef6c4f89aa551eaf265 |
| Delegated to: | Tom Rini |
| Headers | show |
| Series | psci: fix use of clobbered registers in asm | expand |
On Sat, May 27, 2023 at 06:09:42PM -0600, Sam Edwards wrote: > The functions `psci_get_context_id` and `psci_get_target_pc` > are written in C, so the C compiler may clobber registers r0-r3. > Do not use these registers to save data across calls. > > Signed-off-by: Sam Edwards <CFSworks@gmail.com> Applied to u-boot/next, thanks!
diff --git a/arch/arm/cpu/armv7/psci.S b/arch/arm/cpu/armv7/psci.S index 6c066e50d9..41428728b7 100644 --- a/arch/arm/cpu/armv7/psci.S +++ b/arch/arm/cpu/armv7/psci.S @@ -311,11 +311,11 @@ ENTRY(psci_cpu_entry) bl psci_arch_cpu_entry bl psci_get_cpu_id @ CPU ID => r0 - mov r2, r0 @ CPU ID => r2 bl psci_get_context_id @ context id => r0 - mov r1, r0 @ context id => r1 - mov r0, r2 @ CPU ID => r0 + push {r0} @ save context id + bl psci_get_cpu_id @ CPU ID => r0 bl psci_get_target_pc @ target PC => r0 + pop {r1} @ context id => r1 b _do_nonsec_entry ENDPROC(psci_cpu_entry)
The functions `psci_get_context_id` and `psci_get_target_pc` are written in C, so the C compiler may clobber registers r0-r3. Do not use these registers to save data across calls. Signed-off-by: Sam Edwards <CFSworks@gmail.com> --- arch/arm/cpu/armv7/psci.S | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)