iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

powerpc/ftrace: Pass the correct stack pointer for DYNAMIC_FTRACE_WITH_REGS

Browse Source 
commit a4979a7e71eb8da976cbe4a0a1fa50636e76b04f upstream.

For DYNAMIC_FTRACE_WITH_REGS, we should be passing-in the original set
of registers in pt_regs, to capture the state _before_ ftrace_caller.
However, we are instead passing the stack pointer *after* allocating a
stack frame in ftrace_caller. Fix this by saving the proper value of r1
in pt_regs. Also, use SAVE_10GPRS() to simplify the code.

Fixes: 153086644fd1 ("powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Naveen N. Rao 2017-06-01 16:18:16 +05:30 committed by Greg Kroah-Hartman
parent f89f25b531
commit c76655fb0f
1 changed files with 12 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
arch/powerpc/kernel/entry_64.S
View File

@ -1235,10 +1235,14 @@ _GLOBAL(ftrace_caller)
stdu r1,-SWITCH_FRAME_SIZE(r1)
/* Save all gprs to pt_regs */
SAVE_8GPRS(0,r1)
SAVE_8GPRS(8,r1)
SAVE_8GPRS(16,r1)
SAVE_8GPRS(24,r1)
SAVE_GPR(0, r1)
SAVE_10GPRS(2, r1)
SAVE_10GPRS(12, r1)
SAVE_10GPRS(22, r1)
/* Save previous stack pointer (r1) */
addi r8, r1, SWITCH_FRAME_SIZE
std r8, GPR1(r1)
/* Load special regs for save below */
mfmsr r8
@ -1292,10 +1296,10 @@ ftrace_call:
#endif
/* Restore gprs */
REST_8GPRS(0,r1)
REST_8GPRS(8,r1)
REST_8GPRS(16,r1)
REST_8GPRS(24,r1)
REST_GPR(0,r1)
REST_10GPRS(2,r1)
REST_10GPRS(12,r1)
REST_10GPRS(22,r1)
/* Restore callee's TOC */
ld r2, 24(r1)