lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <202509112118.1NElSKNk-lkp@intel.com>
Date: Thu, 11 Sep 2025 21:24:23 +0800
From: kernel test robot <lkp@...el.com>
To: Justinien Bouron <jbouron@...zon.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Baoquan He <bhe@...hat.com>,
	"Rafael J . Wysocki" <rafael.j.wysocki@...el.com>,
	Petr Mladek <pmladek@...e.com>,
	Mario Limonciello <mario.limonciello@....com>,
	Marcos Paulo de Souza <mpdesouza@...e.com>,
	Alexander Graf <graf@...zon.com>,
	Steven Chen <chenste@...ux.microsoft.com>,
	Yan Zhao <yan.y.zhao@...el.com>, kexec@...ts.infradead.org,
	linux-kernel@...r.kernel.org
Cc: llvm@...ts.linux.dev, oe-kbuild-all@...ts.linux.dev,
	Linux Memory Management List <linux-mm@...ck.org>,
	Gunnar Kudrjavets <gunnarku@...zon.com>
Subject: Re: [PATCH] kexec_core: Remove superfluous page offset handling in
 segment loading

Hi Justinien,

kernel test robot noticed the following build warnings:

[auto build test WARNING on akpm-mm/mm-everything]
[also build test WARNING on linus/master v6.17-rc5 next-20250911]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Justinien-Bouron/kexec_core-Remove-superfluous-page-offset-handling-in-segment-loading/20250911-003354
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/20250910163116.49148-1-jbouron%40amazon.com
patch subject: [PATCH] kexec_core: Remove superfluous page offset handling in segment loading
config: x86_64-buildonly-randconfig-004-20250911 (https://download.01.org/0day-ci/archive/20250911/202509112118.1NElSKNk-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250911/202509112118.1NElSKNk-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@...el.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509112118.1NElSKNk-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> kernel/kexec_core.c:745:16: warning: variable 'maddr' set but not used [-Wunused-but-set-variable]
     745 |         unsigned long maddr;
         |                       ^
   1 warning generated.


vim +/maddr +745 kernel/kexec_core.c

2965faa5e03d1e Dave Young       2015-09-09  739  
07d24902977e47 Alexander Graf   2025-06-10  740  static int kimage_load_cma_segment(struct kimage *image, int idx)
07d24902977e47 Alexander Graf   2025-06-10  741  {
07d24902977e47 Alexander Graf   2025-06-10  742  	struct kexec_segment *segment = &image->segment[idx];
07d24902977e47 Alexander Graf   2025-06-10  743  	struct page *cma = image->segment_cma[idx];
07d24902977e47 Alexander Graf   2025-06-10  744  	char *ptr = page_address(cma);
07d24902977e47 Alexander Graf   2025-06-10 @745  	unsigned long maddr;
07d24902977e47 Alexander Graf   2025-06-10  746  	size_t ubytes, mbytes;
07d24902977e47 Alexander Graf   2025-06-10  747  	int result = 0;
07d24902977e47 Alexander Graf   2025-06-10  748  	unsigned char __user *buf = NULL;
07d24902977e47 Alexander Graf   2025-06-10  749  	unsigned char *kbuf = NULL;
07d24902977e47 Alexander Graf   2025-06-10  750  
07d24902977e47 Alexander Graf   2025-06-10  751  	if (image->file_mode)
07d24902977e47 Alexander Graf   2025-06-10  752  		kbuf = segment->kbuf;
07d24902977e47 Alexander Graf   2025-06-10  753  	else
07d24902977e47 Alexander Graf   2025-06-10  754  		buf = segment->buf;
07d24902977e47 Alexander Graf   2025-06-10  755  	ubytes = segment->bufsz;
07d24902977e47 Alexander Graf   2025-06-10  756  	mbytes = segment->memsz;
07d24902977e47 Alexander Graf   2025-06-10  757  	maddr = segment->mem;
07d24902977e47 Alexander Graf   2025-06-10  758  
07d24902977e47 Alexander Graf   2025-06-10  759  	/* Then copy from source buffer to the CMA one */
07d24902977e47 Alexander Graf   2025-06-10  760  	while (mbytes) {
07d24902977e47 Alexander Graf   2025-06-10  761  		size_t uchunk, mchunk;
07d24902977e47 Alexander Graf   2025-06-10  762  
b4cdefb6ef1453 Justinien Bouron 2025-09-10  763  		mchunk = min_t(size_t, mbytes, PAGE_SIZE);
07d24902977e47 Alexander Graf   2025-06-10  764  		uchunk = min(ubytes, mchunk);
07d24902977e47 Alexander Graf   2025-06-10  765  
07d24902977e47 Alexander Graf   2025-06-10  766  		if (uchunk) {
07d24902977e47 Alexander Graf   2025-06-10  767  			/* For file based kexec, source pages are in kernel memory */
07d24902977e47 Alexander Graf   2025-06-10  768  			if (image->file_mode)
07d24902977e47 Alexander Graf   2025-06-10  769  				memcpy(ptr, kbuf, uchunk);
07d24902977e47 Alexander Graf   2025-06-10  770  			else
07d24902977e47 Alexander Graf   2025-06-10  771  				result = copy_from_user(ptr, buf, uchunk);
07d24902977e47 Alexander Graf   2025-06-10  772  			ubytes -= uchunk;
07d24902977e47 Alexander Graf   2025-06-10  773  			if (image->file_mode)
07d24902977e47 Alexander Graf   2025-06-10  774  				kbuf += uchunk;
07d24902977e47 Alexander Graf   2025-06-10  775  			else
07d24902977e47 Alexander Graf   2025-06-10  776  				buf += uchunk;
07d24902977e47 Alexander Graf   2025-06-10  777  		}
07d24902977e47 Alexander Graf   2025-06-10  778  
07d24902977e47 Alexander Graf   2025-06-10  779  		if (result) {
07d24902977e47 Alexander Graf   2025-06-10  780  			result = -EFAULT;
07d24902977e47 Alexander Graf   2025-06-10  781  			goto out;
07d24902977e47 Alexander Graf   2025-06-10  782  		}
07d24902977e47 Alexander Graf   2025-06-10  783  
07d24902977e47 Alexander Graf   2025-06-10  784  		ptr    += mchunk;
07d24902977e47 Alexander Graf   2025-06-10  785  		maddr  += mchunk;
07d24902977e47 Alexander Graf   2025-06-10  786  		mbytes -= mchunk;
07d24902977e47 Alexander Graf   2025-06-10  787  
07d24902977e47 Alexander Graf   2025-06-10  788  		cond_resched();
07d24902977e47 Alexander Graf   2025-06-10  789  	}
07d24902977e47 Alexander Graf   2025-06-10  790  
07d24902977e47 Alexander Graf   2025-06-10  791  	/* Clear any remainder */
07d24902977e47 Alexander Graf   2025-06-10  792  	memset(ptr, 0, mbytes);
07d24902977e47 Alexander Graf   2025-06-10  793  
07d24902977e47 Alexander Graf   2025-06-10  794  out:
07d24902977e47 Alexander Graf   2025-06-10  795  	return result;
07d24902977e47 Alexander Graf   2025-06-10  796  }
07d24902977e47 Alexander Graf   2025-06-10  797  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ