linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [tglx-devel:depthtracking 35/38] arch/x86/kernel/callthunks.c:411:7: warning: variable 'ret' is used uninitialized whenever 'if' condition is true
@ 2022-07-14 12:23 kernel test robot
  2022-08-02 16:13 ` Nick Desaulniers
  0 siblings, 1 reply; 2+ messages in thread
From: kernel test robot @ 2022-07-14 12:23 UTC (permalink / raw)
  To: Peter Zijlstra; +Cc: llvm, kbuild-all, linux-kernel, Thomas Gleixner

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git depthtracking
head:   81d2c1b17a61bfeca4b92a5d6e1fb6f5ff464826
commit: 57b6f2ca7edda679f0a9fe58087ecc9dd9f8dafb [35/38] kprobes: Add callthunk blacklisting
config: x86_64-randconfig-a005 (https://download.01.org/0day-ci/archive/20220714/202207142029.dpdKYPLD-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 5e61b9c556267086ef9b743a0b57df302eef831b)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git/commit/?id=57b6f2ca7edda679f0a9fe58087ecc9dd9f8dafb
        git remote add tglx-devel https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git
        git fetch --no-tags tglx-devel depthtracking
        git checkout 57b6f2ca7edda679f0a9fe58087ecc9dd9f8dafb
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash arch/x86/kernel/

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> arch/x86/kernel/callthunks.c:411:7: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
                   if (!vbuf)
                       ^~~~~
   arch/x86/kernel/callthunks.c:475:9: note: uninitialized use occurs here
           return ret;
                  ^~~
   arch/x86/kernel/callthunks.c:411:3: note: remove the 'if' if its condition is always false
                   if (!vbuf)
                   ^~~~~~~~~~
   arch/x86/kernel/callthunks.c:375:9: note: initialize the variable 'ret' to silence this warning
           int ret, text_size, size;
                  ^
                   = 0
   1 warning generated.


vim +411 arch/x86/kernel/callthunks.c

25cd68b763b44e Thomas Gleixner 2022-06-18  367  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  368  static __init_or_module int callthunks_setup(struct callthunk_sites *cs,
02b09aaafc9a43 Thomas Gleixner 2022-06-18  369  					     struct module_layout *layout)
02b09aaafc9a43 Thomas Gleixner 2022-06-18  370  {
02b09aaafc9a43 Thomas Gleixner 2022-06-18  371  	u8 *tp, *thunk, *buffer, *vbuf = NULL;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  372  	struct paravirt_patch_site *pv;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  373  	unsigned int nthunks, bitpos;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  374  	struct thunk_mem_area *area;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  375  	int ret, text_size, size;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  376  	s32 *s;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  377  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  378  	lockdep_assert_held(&text_mutex);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  379  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  380  	prdbg("Setup %s\n", layout_getname(layout));
02b09aaafc9a43 Thomas Gleixner 2022-06-18  381  	/* Calculate the number of thunks required */
02b09aaafc9a43 Thomas Gleixner 2022-06-18  382  	nthunks = cs->syms_end - cs->syms_start;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  383  	nthunks += cs->pv_end - cs->pv_start;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  384  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  385  	/*
02b09aaafc9a43 Thomas Gleixner 2022-06-18  386  	 * thunk_size can be 0 when there are no intra module calls,
02b09aaafc9a43 Thomas Gleixner 2022-06-18  387  	 * but there might be still sites to patch.
02b09aaafc9a43 Thomas Gleixner 2022-06-18  388  	 */
02b09aaafc9a43 Thomas Gleixner 2022-06-18  389  	if (!nthunks)
02b09aaafc9a43 Thomas Gleixner 2022-06-18  390  		goto patch;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  391  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  392  	area = callthunks_alloc(nthunks);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  393  	if (!area)
02b09aaafc9a43 Thomas Gleixner 2022-06-18  394  		return -ENOMEM;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  395  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  396  	bitpos = area->start;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  397  	thunk = area->tmem->base + bitpos * callthunk_desc.thunk_size;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  398  	tp = thunk;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  399  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  400  	prdbg("Thunk %px\n", tp);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  401  	/*
02b09aaafc9a43 Thomas Gleixner 2022-06-18  402  	 * If the memory area is already RX, use a temporary
02b09aaafc9a43 Thomas Gleixner 2022-06-18  403  	 * buffer. Otherwise just copy into the unused area
02b09aaafc9a43 Thomas Gleixner 2022-06-18  404  	 */
02b09aaafc9a43 Thomas Gleixner 2022-06-18  405  	if (!area->tmem->is_rx) {
02b09aaafc9a43 Thomas Gleixner 2022-06-18  406  		prdbg("Using thunk direct\n");
02b09aaafc9a43 Thomas Gleixner 2022-06-18  407  		buffer = thunk;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  408  	} else {
02b09aaafc9a43 Thomas Gleixner 2022-06-18  409  		size = nthunks * callthunk_desc.thunk_size;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  410  		vbuf = vmalloc(size);
02b09aaafc9a43 Thomas Gleixner 2022-06-18 @411  		if (!vbuf)
02b09aaafc9a43 Thomas Gleixner 2022-06-18  412  			goto fail;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  413  		memset(vbuf, INT3_INSN_OPCODE, size);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  414  		buffer = vbuf;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  415  		prdbg("Using thunk vbuf %px\n", vbuf);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  416  	}
02b09aaafc9a43 Thomas Gleixner 2022-06-18  417  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  418  	for (s = cs->syms_start; s < cs->syms_end; s++, bitpos++) {
02b09aaafc9a43 Thomas Gleixner 2022-06-18  419  		void *dest = (void *)s + *s;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  420  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  421  		ret = callthunk_setup_one(dest, tp, buffer, layout);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  422  		if (ret)
02b09aaafc9a43 Thomas Gleixner 2022-06-18  423  			goto fail;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  424  		buffer += callthunk_desc.thunk_size;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  425  		tp += callthunk_desc.thunk_size;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  426  		bitmap_set(area->tmem->map, bitpos, 1);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  427  		area->nthunks++;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  428  	}
02b09aaafc9a43 Thomas Gleixner 2022-06-18  429  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  430  	for (pv = cs->pv_start; pv < cs->pv_end; pv++, bitpos++) {
02b09aaafc9a43 Thomas Gleixner 2022-06-18  431  		ret = callthunk_setup_one(pv->instr, tp, buffer, layout);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  432  		if (ret)
02b09aaafc9a43 Thomas Gleixner 2022-06-18  433  			goto fail;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  434  		buffer += callthunk_desc.thunk_size;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  435  		tp += callthunk_desc.thunk_size;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  436  		bitmap_set(area->tmem->map, bitpos, 1);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  437  		area->nthunks++;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  438  	}
02b09aaafc9a43 Thomas Gleixner 2022-06-18  439  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  440  	text_size = tp - thunk;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  441  	prdbg("Thunk %px .. %px 0x%x\n", thunk, tp, text_size);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  442  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  443  	/*
02b09aaafc9a43 Thomas Gleixner 2022-06-18  444  	 * If thunk memory is already RX, poke the buffer into it.
02b09aaafc9a43 Thomas Gleixner 2022-06-18  445  	 * Otherwise make the memory RX.
02b09aaafc9a43 Thomas Gleixner 2022-06-18  446  	 */
02b09aaafc9a43 Thomas Gleixner 2022-06-18  447  	if (vbuf)
02b09aaafc9a43 Thomas Gleixner 2022-06-18  448  		text_poke_copy_locked(thunk, vbuf, text_size);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  449  	else
02b09aaafc9a43 Thomas Gleixner 2022-06-18  450  		callthunk_area_set_rx(area);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  451  	sync_core();
02b09aaafc9a43 Thomas Gleixner 2022-06-18  452  
25cd68b763b44e Thomas Gleixner 2022-06-18  453  	ret = callthunk_set_modname(layout);
25cd68b763b44e Thomas Gleixner 2022-06-18  454  	if (ret)
25cd68b763b44e Thomas Gleixner 2022-06-18  455  		goto fail;
25cd68b763b44e Thomas Gleixner 2022-06-18  456  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  457  	layout->base = thunk;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  458  	layout->size = text_size;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  459  	layout->text_size = text_size;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  460  	layout->arch_data = area;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  461  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  462  	vfree(vbuf);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  463  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  464  patch:
02b09aaafc9a43 Thomas Gleixner 2022-06-18  465  	prdbg("Patching call sites %s\n", layout_getname(layout));
02b09aaafc9a43 Thomas Gleixner 2022-06-18  466  	patch_call_sites(cs->call_start, cs->call_end, layout);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  467  	patch_paravirt_call_sites(cs->pv_start, cs->pv_end, layout);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  468  	prdbg("Patching call sites done%s\n", layout_getname(layout));
02b09aaafc9a43 Thomas Gleixner 2022-06-18  469  	return 0;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  470  
02b09aaafc9a43 Thomas Gleixner 2022-06-18  471  fail:
02b09aaafc9a43 Thomas Gleixner 2022-06-18  472  	WARN_ON_ONCE(ret);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  473  	callthunk_free(area, false);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  474  	vfree(vbuf);
02b09aaafc9a43 Thomas Gleixner 2022-06-18  475  	return ret;
02b09aaafc9a43 Thomas Gleixner 2022-06-18  476  }
02b09aaafc9a43 Thomas Gleixner 2022-06-18  477  

:::::: The code at line 411 was first introduced by commit
:::::: 02b09aaafc9a439ca50cc049e98f7cc945e5b294 x86/callthunks: Add call patching for call depth tracking

:::::: TO: Thomas Gleixner <tglx@linutronix.de>
:::::: CC: Thomas Gleixner <tglx@linutronix.de>

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [tglx-devel:depthtracking 35/38] arch/x86/kernel/callthunks.c:411:7: warning: variable 'ret' is used uninitialized whenever 'if' condition is true
  2022-07-14 12:23 [tglx-devel:depthtracking 35/38] arch/x86/kernel/callthunks.c:411:7: warning: variable 'ret' is used uninitialized whenever 'if' condition is true kernel test robot
@ 2022-08-02 16:13 ` Nick Desaulniers
  0 siblings, 0 replies; 2+ messages in thread
From: Nick Desaulniers @ 2022-08-02 16:13 UTC (permalink / raw)
  To: Thomas Gleixner
  Cc: Peter Zijlstra, llvm, kbuild-all, linux-kernel, kernel test robot

On Thu, Jul 14, 2022 at 5:24 AM kernel test robot <lkp@intel.com> wrote:
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git depthtracking
> head:   81d2c1b17a61bfeca4b92a5d6e1fb6f5ff464826
> commit: 57b6f2ca7edda679f0a9fe58087ecc9dd9f8dafb [35/38] kprobes: Add callthunk blacklisting
> config: x86_64-randconfig-a005 (https://download.01.org/0day-ci/archive/20220714/202207142029.dpdKYPLD-lkp@intel.com/config)
> compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 5e61b9c556267086ef9b743a0b57df302eef831b)
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git/commit/?id=57b6f2ca7edda679f0a9fe58087ecc9dd9f8dafb
>         git remote add tglx-devel https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git
>         git fetch --no-tags tglx-devel depthtracking
>         git checkout 57b6f2ca7edda679f0a9fe58087ecc9dd9f8dafb
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash arch/x86/kernel/
>
> If you fix the issue, kindly add following tag where applicable
> Reported-by: kernel test robot <lkp@intel.com>
>
> All warnings (new ones prefixed by >>):
>
> >> arch/x86/kernel/callthunks.c:411:7: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
>                    if (!vbuf)
>                        ^~~~~
>    arch/x86/kernel/callthunks.c:475:9: note: uninitialized use occurs here
>            return ret;
>                   ^~~
>    arch/x86/kernel/callthunks.c:411:3: note: remove the 'if' if its condition is always false
>                    if (!vbuf)
>                    ^~~~~~~~~~
>    arch/x86/kernel/callthunks.c:375:9: note: initialize the variable 'ret' to silence this warning
>            int ret, text_size, size;
>                   ^
>                    = 0
>    1 warning generated.
>
>
> vim +411 arch/x86/kernel/callthunks.c

Looks legit.

>
> 25cd68b763b44e Thomas Gleixner 2022-06-18  367
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  368  static __init_or_module int callthunks_setup(struct callthunk_sites *cs,
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  369                                               struct module_layout *layout)
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  370  {
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  371          u8 *tp, *thunk, *buffer, *vbuf = NULL;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  372          struct paravirt_patch_site *pv;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  373          unsigned int nthunks, bitpos;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  374          struct thunk_mem_area *area;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  375          int ret, text_size, size;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  376          s32 *s;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  377
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  378          lockdep_assert_held(&text_mutex);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  379
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  380          prdbg("Setup %s\n", layout_getname(layout));
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  381          /* Calculate the number of thunks required */
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  382          nthunks = cs->syms_end - cs->syms_start;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  383          nthunks += cs->pv_end - cs->pv_start;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  384
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  385          /*
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  386           * thunk_size can be 0 when there are no intra module calls,
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  387           * but there might be still sites to patch.
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  388           */
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  389          if (!nthunks)
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  390                  goto patch;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  391
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  392          area = callthunks_alloc(nthunks);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  393          if (!area)
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  394                  return -ENOMEM;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  395
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  396          bitpos = area->start;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  397          thunk = area->tmem->base + bitpos * callthunk_desc.thunk_size;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  398          tp = thunk;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  399
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  400          prdbg("Thunk %px\n", tp);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  401          /*
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  402           * If the memory area is already RX, use a temporary
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  403           * buffer. Otherwise just copy into the unused area
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  404           */
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  405          if (!area->tmem->is_rx) {
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  406                  prdbg("Using thunk direct\n");
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  407                  buffer = thunk;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  408          } else {
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  409                  size = nthunks * callthunk_desc.thunk_size;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  410                  vbuf = vmalloc(size);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18 @411                  if (!vbuf)
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  412                          goto fail;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  413                  memset(vbuf, INT3_INSN_OPCODE, size);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  414                  buffer = vbuf;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  415                  prdbg("Using thunk vbuf %px\n", vbuf);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  416          }
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  417
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  418          for (s = cs->syms_start; s < cs->syms_end; s++, bitpos++) {
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  419                  void *dest = (void *)s + *s;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  420
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  421                  ret = callthunk_setup_one(dest, tp, buffer, layout);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  422                  if (ret)
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  423                          goto fail;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  424                  buffer += callthunk_desc.thunk_size;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  425                  tp += callthunk_desc.thunk_size;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  426                  bitmap_set(area->tmem->map, bitpos, 1);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  427                  area->nthunks++;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  428          }
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  429
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  430          for (pv = cs->pv_start; pv < cs->pv_end; pv++, bitpos++) {
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  431                  ret = callthunk_setup_one(pv->instr, tp, buffer, layout);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  432                  if (ret)
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  433                          goto fail;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  434                  buffer += callthunk_desc.thunk_size;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  435                  tp += callthunk_desc.thunk_size;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  436                  bitmap_set(area->tmem->map, bitpos, 1);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  437                  area->nthunks++;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  438          }
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  439
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  440          text_size = tp - thunk;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  441          prdbg("Thunk %px .. %px 0x%x\n", thunk, tp, text_size);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  442
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  443          /*
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  444           * If thunk memory is already RX, poke the buffer into it.
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  445           * Otherwise make the memory RX.
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  446           */
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  447          if (vbuf)
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  448                  text_poke_copy_locked(thunk, vbuf, text_size);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  449          else
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  450                  callthunk_area_set_rx(area);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  451          sync_core();
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  452
> 25cd68b763b44e Thomas Gleixner 2022-06-18  453          ret = callthunk_set_modname(layout);
> 25cd68b763b44e Thomas Gleixner 2022-06-18  454          if (ret)
> 25cd68b763b44e Thomas Gleixner 2022-06-18  455                  goto fail;
> 25cd68b763b44e Thomas Gleixner 2022-06-18  456
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  457          layout->base = thunk;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  458          layout->size = text_size;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  459          layout->text_size = text_size;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  460          layout->arch_data = area;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  461
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  462          vfree(vbuf);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  463
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  464  patch:
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  465          prdbg("Patching call sites %s\n", layout_getname(layout));
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  466          patch_call_sites(cs->call_start, cs->call_end, layout);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  467          patch_paravirt_call_sites(cs->pv_start, cs->pv_end, layout);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  468          prdbg("Patching call sites done%s\n", layout_getname(layout));
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  469          return 0;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  470
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  471  fail:
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  472          WARN_ON_ONCE(ret);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  473          callthunk_free(area, false);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  474          vfree(vbuf);
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  475          return ret;
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  476  }
> 02b09aaafc9a43 Thomas Gleixner 2022-06-18  477
>
> :::::: The code at line 411 was first introduced by commit
> :::::: 02b09aaafc9a439ca50cc049e98f7cc945e5b294 x86/callthunks: Add call patching for call depth tracking
>
> :::::: TO: Thomas Gleixner <tglx@linutronix.de>
> :::::: CC: Thomas Gleixner <tglx@linutronix.de>
>
> --
> 0-DAY CI Kernel Test Service
> https://01.org/lkp
>


-- 
Thanks,
~Nick Desaulniers

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2022-08-02 16:17 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-07-14 12:23 [tglx-devel:depthtracking 35/38] arch/x86/kernel/callthunks.c:411:7: warning: variable 'ret' is used uninitialized whenever 'if' condition is true kernel test robot
2022-08-02 16:13 ` Nick Desaulniers

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).