This is a note to let you know that I've just added the patch titled powerpc/ftrace: Fix stack teardown in ftrace_no_trace to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-ftrace-fix-stack-teardown-in-ftrace_no_trace.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From stable+bounces-6808-greg=kroah.com@xxxxxxxxxxxxxxx Fri Dec 15 12:18:31 2023 From: Naveen N Rao <naveen@xxxxxxxxxx> Date: Fri, 15 Dec 2023 16:44:33 +0530 Subject: powerpc/ftrace: Fix stack teardown in ftrace_no_trace To: <stable@xxxxxxxxxxxxxxx> Cc: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>, Michael Ellerman <mpe@xxxxxxxxxxxxxx> Message-ID: <20231215111433.2362641-2-naveen@xxxxxxxxxx> From: Naveen N Rao <naveen@xxxxxxxxxx> commit 4b3338aaa74d7d4ec5b6734dc298f0db94ec83d2 upstream. Commit 41a506ef71eb ("powerpc/ftrace: Create a dummy stackframe to fix stack unwind") added use of a new stack frame on ftrace entry to fix stack unwind. However, the commit missed updating the offset used while tearing down the ftrace stack when ftrace is disabled. Fix the same. In addition, the commit missed saving the correct stack pointer in pt_regs. Update the same. Fixes: 41a506ef71eb ("powerpc/ftrace: Create a dummy stackframe to fix stack unwind") Cc: stable@xxxxxxxxxxxxxxx # v6.5+ Signed-off-by: Naveen N Rao <naveen@xxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://msgid.link/20231130065947.2188860-1-naveen@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S +++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S @@ -59,7 +59,7 @@ _GLOBAL(ftrace_regs_caller) SAVE_10GPRS(22, r1) /* Save previous stack pointer (r1) */ - addi r8, r1, SWITCH_FRAME_SIZE + addi r8, r1, SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE std r8, GPR1(r1) /* Load special regs for save below */ @@ -154,7 +154,7 @@ ftrace_no_trace: mflr r3 mtctr r3 REST_GPR(3, r1) - addi r1, r1, SWITCH_FRAME_SIZE + addi r1, r1, SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE mtlr r0 bctr Patches currently in stable-queue which might be from kroah.com@xxxxxxxxxxxxxxx are queue-4.19/powerpc-ftrace-create-a-dummy-stackframe-to-fix-stack-unwind.patch queue-4.19/powerpc-ftrace-fix-stack-teardown-in-ftrace_no_trace.patch