Hi, [auto build test ERROR on stable/master] [also build test ERROR on v4.7-rc7] [cannot apply to next-20160721] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/zhongjiang/kexec-add-resriction-on-the-kexec_load/20160722-143017 base: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git master config: i386-defconfig (attached as .config) compiler: gcc-6 (Debian 6.1.1-9) 6.1.1 20160705 reproduce: # save the attached .config to linux build tree make ARCH=i386 All error/warnings (new ones prefixed by >>): kernel/kexec_core.c: In function 'sanity_check_segment_list': >> kernel/kexec_core.c:222:3: error: 'total' undeclared (first use in this function) total += image->segment[i].memsz; ^~~~~ kernel/kexec_core.c:222:3: note: each undeclared identifier is reported only once for each function it appears in >> kernel/kexec_core.c:151:16: warning: unused variable 'total_segments' [-Wunused-variable] unsigned long total_segments = 0; ^~~~~~~~~~~~~~ vim +/total +222 kernel/kexec_core.c 145 gfp_t gfp_mask, 146 unsigned long dest); 147 148 int sanity_check_segment_list(struct kimage *image) 149 { 150 int result, i; > 151 unsigned long total_segments = 0; 152 unsigned long nr_segments = image->nr_segments; 153 154 /* 155 * Verify we have good destination addresses. The caller is 156 * responsible for making certain we don't attempt to load 157 * the new image into invalid or reserved areas of RAM. This 158 * just verifies it is an address we can use. 159 * 160 * Since the kernel does everything in page size chunks ensure 161 * the destination addresses are page aligned. Too many 162 * special cases crop of when we don't do this. The most 163 * insidious is getting overlapping destination addresses 164 * simply because addresses are changed to page size 165 * granularity. 166 */ 167 result = -EADDRNOTAVAIL; 168 for (i = 0; i < nr_segments; i++) { 169 unsigned long mstart, mend; 170 171 mstart = image->segment[i].mem; 172 mend = mstart + image->segment[i].memsz; 173 if ((mstart & ~PAGE_MASK) || (mend & ~PAGE_MASK)) 174 return result; 175 if (mend >= KEXEC_DESTINATION_MEMORY_LIMIT) 176 return result; 177 } 178 179 /* Verify our destination addresses do not overlap. 180 * If we alloed overlapping destination addresses 181 * through very weird things can happen with no 182 * easy explanation as one segment stops on another. 183 */ 184 result = -EINVAL; 185 for (i = 0; i < nr_segments; i++) { 186 unsigned long mstart, mend; 187 unsigned long j; 188 189 mstart = image->segment[i].mem; 190 mend = mstart + image->segment[i].memsz; 191 for (j = 0; j < i; j++) { 192 unsigned long pstart, pend; 193 194 pstart = image->segment[j].mem; 195 pend = pstart + image->segment[j].memsz; 196 /* Do the segments overlap ? */ 197 if ((mend > pstart) && (mstart < pend)) 198 return result; 199 } 200 } 201 202 /* Ensure our buffer sizes are strictly less than 203 * our memory sizes. This should always be the case, 204 * and it is easier to check up front than to be surprised 205 * later on. 206 */ 207 result = -EINVAL; 208 for (i = 0; i < nr_segments; i++) { 209 if (image->segment[i].bufsz > image->segment[i].memsz) 210 return result; 211 } 212 213 /* Verity all segment size donnot exceed the specified size. 214 * if segment size from user space is too large, a large 215 * amount of time will be wasted when allocating page. so, 216 * softlockup may be come up. 217 */ 218 for (i = 0; i < nr_segments; i++) { 219 if (image->segment[i].memsz > (totalram_pages / 2)) 220 return result; 221 > 222 total += image->segment[i].memsz; 223 } 224 225 if (total > (totalram_pages / 2)) --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation -------------- next part -------------- A non-text attachment was scrubbed... Name: .config.gz Type: application/octet-stream Size: 24863 bytes Desc: not available URL: <http://lists.infradead.org/pipermail/kexec/attachments/20160722/3bfcc20b/attachment-0001.obj>