diff mbox

[1/7] powerpc: Add CFI information on indirect syscall

Message ID 20180904204553.6971-2-adhemerval.zanella@linaro.org
State Rejected
Delegated to: Tulio Magno Quites Machado Filho
Headers

Commit Message

Adhemerval Zanella Netto Sept. 4, 2018, 8:45 p.m. UTC 
  This patch the required CFI information on powerpc indirect syscall
so backtrace works correctly on signal handler.

Checked on powerpc-linux-gnu and powerpc64le-linux-gnu.

	* sysdeps/unix/sysv/linux/powerpc/syscall.S (syscall): Add CFI
	information.
---
 ChangeLog                                 | 5 +++++
 sysdeps/unix/sysv/linux/powerpc/syscall.S | 1 +
 2 files changed, 6 insertions(+)

Comments

Tulio Magno Quites Machado Filho Sept. 6, 2018, 3:18 p.m. UTC | #1 
Adhemerval Zanella <adhemerval.zanella@linaro.org> writes:

> This patch the required CFI information on powerpc indirect syscall
> so backtrace works correctly on signal handler.
>
> Checked on powerpc-linux-gnu and powerpc64le-linux-gnu.
>
> 	* sysdeps/unix/sysv/linux/powerpc/syscall.S (syscall): Add CFI
> 	information.
> ---
>  ChangeLog                                 | 5 +++++
>  sysdeps/unix/sysv/linux/powerpc/syscall.S | 1 +
>  2 files changed, 6 insertions(+)
>
> diff --git a/sysdeps/unix/sysv/linux/powerpc/syscall.S b/sysdeps/unix/sysv/linux/powerpc/syscall.S
> index 2da91721be..e30f461a17 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/syscall.S
> +++ b/sysdeps/unix/sysv/linux/powerpc/syscall.S
> @@ -19,6 +19,7 @@
>  
>  ENTRY (syscall)
>  	ABORT_TRANSACTION
> +	cfi_def_cfa_offset (0)

Why is this necessary in a function that is defined via ENTRY (or
ENTRY_TOCLESS) that already has cfi_startproc?

Does the error you found mean that parameter simple from cfi_startproc is being
set by mistake?
Adhemerval Zanella Netto Sept. 25, 2018, 9:13 p.m. UTC | #2 
On 06/09/2018 12:18, Tulio Magno Quites Machado Filho wrote:
> Adhemerval Zanella <adhemerval.zanella@linaro.org> writes:
> 
>> This patch the required CFI information on powerpc indirect syscall
>> so backtrace works correctly on signal handler.
>>
>> Checked on powerpc-linux-gnu and powerpc64le-linux-gnu.
>>
>> 	* sysdeps/unix/sysv/linux/powerpc/syscall.S (syscall): Add CFI
>> 	information.
>> ---
>>  ChangeLog                                 | 5 +++++
>>  sysdeps/unix/sysv/linux/powerpc/syscall.S | 1 +
>>  2 files changed, 6 insertions(+)
>>
>> diff --git a/sysdeps/unix/sysv/linux/powerpc/syscall.S b/sysdeps/unix/sysv/linux/powerpc/syscall.S
>> index 2da91721be..e30f461a17 100644
>> --- a/sysdeps/unix/sysv/linux/powerpc/syscall.S
>> +++ b/sysdeps/unix/sysv/linux/powerpc/syscall.S
>> @@ -19,6 +19,7 @@
>>  
>>  ENTRY (syscall)
>>  	ABORT_TRANSACTION
>> +	cfi_def_cfa_offset (0)
> 
> Why is this necessary in a function that is defined via ENTRY (or
> ENTRY_TOCLESS) that already has cfi_startproc?
> 
> Does the error you found mean that parameter simple from cfi_startproc is being
> set by mistake?
> 

Re-testing it on powerpc64le it seems that current cfi directives
provided by ENTRY indeed are suffice.  The cfi_def_cfa_offset came
in fact from a previous iteration, which I initially added a frame 
set/restore.  So I withdraw this patch.
diff mbox

Patch

diff --git a/sysdeps/unix/sysv/linux/powerpc/syscall.S b/sysdeps/unix/sysv/linux/powerpc/syscall.S
index 2da91721be..e30f461a17 100644
--- a/sysdeps/unix/sysv/linux/powerpc/syscall.S
+++ b/sysdeps/unix/sysv/linux/powerpc/syscall.S
@@ -19,6 +19,7 @@ 
 
 ENTRY (syscall)
 	ABORT_TRANSACTION
+	cfi_def_cfa_offset (0)
 	mr   r0,r3
 	mr   r3,r4
 	mr   r4,r5