On 26/04/24 07:57, kernel test robot wrote:
tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head: 5e4f84f18c4ee9b0ccdc19e39b7de41df21699dd
commit: 849599b702ef8977fcd5b2f27c61ef773c42bb88 [7646/8170] powerpc/crash: add crash memory hotplug support
config: powerpc-randconfig-r061-20240426 (https://download.01.org/0day-ci/archive/20240426/202404261048.skfV5DDB-lkp@xxxxxxxxx/config)
compiler: powerpc-linux-gcc (GCC) 13.2.0
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@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202404261048.skfV5DDB-lkp@xxxxxxxxx/
cocci warnings: (new ones prefixed by >>)
arch/powerpc/kexec/crash.c:488:2-8: WARNING: NULL check before some freeing functions is not needed.
vim +488 arch/powerpc/kexec/crash.c
418
419 /**
420 * update_crash_elfcorehdr() - Recreate the elfcorehdr and replace it with old
421 * elfcorehdr in the kexec segment array.
422 * @image: the active struct kimage
423 * @mn: struct memory_notify data handler
424 */
425 static void update_crash_elfcorehdr(struct kimage *image, struct memory_notify *mn)
426 {
427 int ret;
428 struct crash_mem *cmem = NULL;
429 struct kexec_segment *ksegment;
430 void *ptr, *mem, *elfbuf = NULL;
431 unsigned long elfsz, memsz, base_addr, size;
432
433 ksegment = &image->segment[image->elfcorehdr_index];
434 mem = (void *) ksegment->mem;
435 memsz = ksegment->memsz;
436
437 ret = get_crash_memory_ranges(&cmem);
438 if (ret) {
439 pr_err("Failed to get crash mem range\n");
440 return;
441 }
442
443 /*
444 * The hot unplugged memory is part of crash memory ranges,
445 * remove it here.
446 */
447 if (image->hp_action == KEXEC_CRASH_HP_REMOVE_MEMORY) {
448 base_addr = PFN_PHYS(mn->start_pfn);
449 size = mn->nr_pages * PAGE_SIZE;
450 ret = remove_mem_range(&cmem, base_addr, size);
451 if (ret) {
452 pr_err("Failed to remove hot-unplugged memory from crash memory ranges\n");
453 goto out;
454 }
455 }
456
457 ret = crash_prepare_elf64_headers(cmem, false, &elfbuf, &elfsz);
458 if (ret) {
459 pr_err("Failed to prepare elf header\n");
460 goto out;
461 }
462
463 /*
464 * It is unlikely that kernel hit this because elfcorehdr kexec
465 * segment (memsz) is built with addition space to accommodate growing
466 * number of crash memory ranges while loading the kdump kernel. It is
467 * Just to avoid any unforeseen case.
468 */
469 if (elfsz > memsz) {
470 pr_err("Updated crash elfcorehdr elfsz %lu > memsz %lu", elfsz, memsz);
471 goto out;
472 }
473
474 ptr = __va(mem);
475 if (ptr) {
476 /* Temporarily invalidate the crash image while it is replaced */
477 xchg(&kexec_crash_image, NULL);
478
479 /* Replace the old elfcorehdr with newly prepared elfcorehdr */
480 memcpy((void *)ptr, elfbuf, elfsz);
481
482 /* The crash image is now valid once again */
483 xchg(&kexec_crash_image, image);
484 }
485 out:
486 kvfree(cmem);
487 if (elfbuf)
> 488 kvfree(elfbuf);
489 }
490
Thanks for the report.
I will fix this and send next version.
- Sourabh Jain
