| Message ID | 921e8d60c847d42f7309feae1936fa0117b7f0d1.1651905939.git.christophe.leroy@csgroup.eu (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | powerpc: ftrace optimisation and cleanup and more [v2] | expand |
Hi Christophe,
I love your patch! Perhaps something to improve:
[auto build test WARNING on powerpc/next]
[also build test WARNING on powerpc/topic/ppc-kvm v5.18-rc5 next-20220506]
[cannot apply to rostedt-trace/for-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/Christophe-Leroy/powerpc-ftrace-optimisation-and-cleanup-and-more-v2/20220507-145034
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-randconfig-s031-20220506 (https://download.01.org/0day-ci/archive/20220507/202205071900.opHsWE8v-lkp@intel.com/config)
compiler: powerpc-linux-gcc (GCC) 11.3.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# apt-get install sparse
# sparse version: v0.6.4-dirty
# https://github.com/intel-lab-lkp/linux/commit/1c6a385ed330a6ed959cad02f89306fb84e4334c
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Christophe-Leroy/powerpc-ftrace-optimisation-and-cleanup-and-more-v2/20220507-145034
git checkout 1c6a385ed330a6ed959cad02f89306fb84e4334c
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=powerpc SHELL=/bin/bash arch/powerpc/kernel/
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
sparse warnings: (new ones prefixed by >>)
>> arch/powerpc/kernel/module_32.c:298:43: sparse: sparse: incorrect type in argument 1 (different base types) @@ expected struct ppc_inst_t [usertype] *inst @@ got unsigned int * @@
arch/powerpc/kernel/module_32.c:298:43: sparse: expected struct ppc_inst_t [usertype] *inst
arch/powerpc/kernel/module_32.c:298:43: sparse: got unsigned int *
arch/powerpc/kernel/module_32.c:300:49: sparse: sparse: incorrect type in argument 1 (different base types) @@ expected struct ppc_inst_t [usertype] *inst @@ got unsigned int * @@
arch/powerpc/kernel/module_32.c:300:49: sparse: expected struct ppc_inst_t [usertype] *inst
arch/powerpc/kernel/module_32.c:300:49: sparse: got unsigned int *
arch/powerpc/kernel/module_32.c:302:49: sparse: sparse: incorrect type in argument 1 (different base types) @@ expected struct ppc_inst_t [usertype] *inst @@ got unsigned int * @@
arch/powerpc/kernel/module_32.c:302:49: sparse: expected struct ppc_inst_t [usertype] *inst
arch/powerpc/kernel/module_32.c:302:49: sparse: got unsigned int *
arch/powerpc/kernel/module_32.c:304:49: sparse: sparse: incorrect type in argument 1 (different base types) @@ expected struct ppc_inst_t [usertype] *inst @@ got unsigned int * @@
arch/powerpc/kernel/module_32.c:304:49: sparse: expected struct ppc_inst_t [usertype] *inst
arch/powerpc/kernel/module_32.c:304:49: sparse: got unsigned int *
vim +298 arch/powerpc/kernel/module_32.c
290
291 #ifdef CONFIG_DYNAMIC_FTRACE
292 notrace int module_trampoline_target(struct module *mod, unsigned long addr,
293 unsigned long *target)
294 {
295 unsigned int jmp[4];
296
297 /* Find where the trampoline jumps to */
> 298 if (copy_inst_from_kernel_nofault(jmp, (void *)addr))
299 return -EFAULT;
300 if (__copy_inst_from_kernel_nofault(jmp + 1, (void *)addr + 4))
301 return -EFAULT;
302 if (__copy_inst_from_kernel_nofault(jmp + 2, (void *)addr + 8))
303 return -EFAULT;
304 if (__copy_inst_from_kernel_nofault(jmp + 3, (void *)addr + 12))
305 return -EFAULT;
306
307 /* verify that this is what we expect it to be */
308 if ((jmp[0] & 0xffff0000) != PPC_RAW_LIS(_R12, 0) ||
309 (jmp[1] & 0xffff0000) != PPC_RAW_ADDI(_R12, _R12, 0) ||
310 jmp[2] != PPC_RAW_MTCTR(_R12) ||
311 jmp[3] != PPC_RAW_BCTR())
312 return -EINVAL;
313
314 addr = (jmp[1] & 0xffff) | ((jmp[0] & 0xffff) << 16);
315 if (addr & 0x8000)
316 addr -= 0x10000;
317
318 *target = addr;
319
320 return 0;
321 }
322
diff --git a/arch/powerpc/kernel/module_32.c b/arch/powerpc/kernel/module_32.c index a0432ef46967..1b129d728e83 100644 --- a/arch/powerpc/kernel/module_32.c +++ b/arch/powerpc/kernel/module_32.c @@ -289,13 +289,19 @@ int apply_relocate_add(Elf32_Shdr *sechdrs, } #ifdef CONFIG_DYNAMIC_FTRACE -int module_trampoline_target(struct module *mod, unsigned long addr, - unsigned long *target) +notrace int module_trampoline_target(struct module *mod, unsigned long addr, + unsigned long *target) { unsigned int jmp[4]; /* Find where the trampoline jumps to */ - if (copy_from_kernel_nofault(jmp, (void *)addr, sizeof(jmp))) + if (copy_inst_from_kernel_nofault(jmp, (void *)addr)) + return -EFAULT; + if (__copy_inst_from_kernel_nofault(jmp + 1, (void *)addr + 4)) + return -EFAULT; + if (__copy_inst_from_kernel_nofault(jmp + 2, (void *)addr + 8)) + return -EFAULT; + if (__copy_inst_from_kernel_nofault(jmp + 3, (void *)addr + 12)) return -EFAULT; /* verify that this is what we expect it to be */
module_trampoline_target() is quite a hot path used when activating/deactivating function tracer. Avoid the heavy copy_from_kernel_nofault() by doing four calls to copy_inst_from_kernel_nofault(). Use __copy_inst_from_kernel_nofault() for the 3 last calls. First call is done to copy_from_kernel_nofault() to check address is within kernel space. No risk to wrap out the top of kernel space because the last page is never mapped so if address is in last page the first copy will fails and the other ones will never be performed. And also make it notrace just like all functions that call it. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> --- arch/powerpc/kernel/module_32.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)