kernel.git/arch/powerpc/kernel/trace, branch linux-5.18.y

powerpc/ftrace: Remove ftrace init tramp once kernel init is complete

2022-07-02T14:44:55Z

commit 84ade0a6655bee803d176525ef457175cbf4df22 upstream. Stop using the ftrace trampoline for init section once kernel init is complete. Fixes: 67361cf8071286 ("powerpc/ftrace: Handle large kernel configs") Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Naveen N. Rao Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220516071422.463738-1-naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman

powerpc: Move C prototypes out of asm-prototypes.h

2022-03-08T11:06:25Z

We originally added asm-prototypes.h in commit 42f5b4cacd78 ("powerpc: Introduce asm-prototypes.h"). It's purpose was for prototypes of C functions that are only called from asm, in order to fix sparse warnings about missing prototypes. A few months later Nick added a different use case in commit 4efca4ed05cb ("kbuild: modversions for EXPORT_SYMBOL() for asm") for C prototypes for exported asm functions. This is basically the inverse of our original usage. Since then we've added various prototypes to asm-prototypes.h for both reasons, meaning we now need to unstitch it all. Dispatch prototypes of C functions into relevant headers and keep only the prototypes for functions defined in assembly. For the time being, leave prom_init() there because moving it into asm/prom.h or asm/setup.h conflicts with drivers/gpu/drm/nouveau/nvkm/subdev/bios/shadowrom.o This will be fixed later by untaggling asm/pci.h and asm/prom.h or by renaming the function in shadowrom.c Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/62d46904eca74042097acf4cb12c175e3067f3d1.1646413435.git.christophe.leroy@csgroup.eu

powerpc/ftrace: Use STK_GOT in ftrace_mprofile.S

2022-03-07T13:05:01Z

Instead of open coding offset value 24, use STK_GOT when accessing got register in stack. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/9042bb30fa972056715fe5b6598a7c8049681293.1645099283.git.christophe.leroy@csgroup.eu

powerpc/ftrace: Regroup PPC64 specific operations in ftrace_mprofile.S

2022-03-07T13:05:01Z

CONFIG_MPROFILE_KERNEL is only for PPC64 and ftrace_mprofile.o is build on PPC64 only when CONFIG_MPROFILE_KERNEL is defined. Move saving of r0 inside #ifdef PPC64 Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/619dfb672bf4f1b777a4b3f8b4f14e637fea2716.1645099283.git.christophe.leroy@csgroup.eu

powerpc/ftrace: Refactor ftrace_{regs_}caller

2022-03-07T13:05:00Z

ftrace_caller() and frace_regs_caller() have now a lot in common. Refactor them using GAS macros. Signed-off-by: Christophe Leroy Reviewed-by: Naveen N. Rao Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/9d7df9e4fc98a86051489f61d3c9bc67f92f7e27.1645099283.git.christophe.leroy@csgroup.eu

powerpc/ftrace: Don't use lmw/stmw in ftrace_regs_caller()

2022-03-07T13:05:00Z

For the same reason as commit a85c728cb5e1 ("powerpc/32: Don't use lmw/stmw for saving/restoring non volatile regs"), don't use lmw/stmw in ftrace_regs_caller(). Use the same macros for PPC32 and PPC64. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/ec286d2cc6989668a96f14543275437d2f3f0e3a.1645099283.git.christophe.leroy@csgroup.eu

powerpc/ftrace: Style cleanup in ftrace_mprofile.S

2022-02-16T12:09:47Z

Add some line breaks to better match the file's style, add some space after comma and fix a couple of misplaced blanks. Suggested-by: Naveen N. Rao Signed-off-by: Christophe Leroy Reviewed-by: Naveen N. Rao Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/973506292d0c7b05c06530c8e11803ce38e5eda2.1644949750.git.christophe.leroy@csgroup.eu

powerpc/ftrace: Have arch_ftrace_get_regs() return NULL unless FL_SAVE_REGS is set

2022-02-16T12:09:47Z

When FL_SAVE_REGS is not set we get here via ftrace_caller() which doesn't save all registers. ftrace_caller() explicitely clears regs.msr, so we can rely on it to know where we come from. We don't expect MSR register to be 0 at all when involving ftrace. Fixes: 40b035efe288 ("powerpc/ftrace: Implement CONFIG_DYNAMIC_FTRACE_WITH_ARGS") Reported-by: Naveen N. Rao Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/2f9a7e898c93cc7438ef5ccd47cb9c3a9c5b53ef.1644949750.git.christophe.leroy@csgroup.eu

powerpc/ftrace: Add recursion protection in prepare_ftrace_return()

2022-02-16T12:09:47Z

The function_graph_enter() does not provide any recursion protection. Add a protection in prepare_ftrace_return() in case function_graph_enter() calls something that gets function graph traced. Fixes: 830213786c49 ("powerpc/ftrace: directly call of function graph tracer by ftrace caller") Reported-by: Naveen N. Rao Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/74edf2ff0a60e66b0d9225a137100a86a0557032.1644949750.git.christophe.leroy@csgroup.eu

powerpc/ftrace: Also save r1 in ftrace_caller()

2022-02-16T12:09:47Z

Also save r1 in ftrace_caller() r1 is needed during unwinding when the function_graph tracer is active. Fixes: 830213786c49 ("powerpc/ftrace: directly call of function graph tracer by ftrace caller") Reported-by: Naveen N. Rao Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/ff535e86d3a69376a6d89168511d4e403835f18b.1644949750.git.christophe.leroy@csgroup.eu