On 04/16/18 at 10:57am, Dave Young wrote: > On 04/13/18 at 02:27pm, Lee, Chun-Yi wrote: > > When using kdump, SOMETIMES the "size not consistent" warning message > > shows up when the crash kernel boots with early_ioremap_debug parameter: > > > > WARNING: CPU: 0 PID: 0 at ../mm/early_ioremap.c:182 early_iounmap+0x4f/0x12c() > > early_iounmap(ffffffffff200180, 00000118) [0] size not consistent 00000120 > > > > The root cause is that the unmapping size of memory map doesn't > > match with the original size when mapping: > > > > in __efi_memmap_init() > > map.map = early_memremap(phys_map, data->size); > > > > in efi_memmap_unmap() > > size = efi.memmap.desc_size * efi.memmap.nr_map; > > early_memunmap(efi.memmap.map, size); > > > > But the efi.memmap.nr_map is from __efi_memmap_init(). The remainder > > of size was discarded when calculating the nr_map: > > map.nr_map = data->size / data->desc_size; > > > > When the original size of memory map region does not equal to the > > result of multiplication. The "size not consistent" warning > > will be triggered. > > > > This issue sometimes was hit by kdump because kexec set the efi map > > size to align with 16 when loading crash kernel image: > > > > in bzImage64_load() > > efi_map_sz = efi_get_runtime_map_size(); > > efi_map_sz = ALIGN(efi_map_sz, 16); > > > > This patch changes the logic in the unmapping function. Using the > > end address of map to calcuate original size. > > > > Thank Randy Wright for his report and testing. And also thank > > Takashi Iwai for his help to trace issue. > > Good catch. The kexec code need to be fixed to use a separate buffer so > avoid the alignment like what kexec-tools did. I can submit a fix for > that. Can you try below code, see if it works? diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c index 3182908b7e6c..eaee37c54b7b 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -398,11 +398,10 @@ static void *bzImage64_load(struct kimage *image, char *kernel, * little bit simple */ efi_map_sz = efi_get_runtime_map_size(); - efi_map_sz = ALIGN(efi_map_sz, 16); params_cmdline_sz = sizeof(struct boot_params) + cmdline_len + MAX_ELFCOREHDR_STR_LEN; params_cmdline_sz = ALIGN(params_cmdline_sz, 16); - kbuf.bufsz = params_cmdline_sz + efi_map_sz + + kbuf.bufsz = params_cmdline_sz + ALIGN(efi_map_sz, 16)+ sizeof(struct setup_data) + sizeof(struct efi_setup_data); @@ -410,7 +409,7 @@ static void *bzImage64_load(struct kimage *image, char *kernel, if (!params) return ERR_PTR(-ENOMEM); efi_map_offset = params_cmdline_sz; - efi_setup_data_offset = efi_map_offset + efi_map_sz; + efi_setup_data_offset = efi_map_offset + ALIGN(efi_map_sz, 16); /* Copy setup header onto bootparams. Documentation/x86/boot.txt */ setup_header_size = 0x0202 + kernel[0x0201] - setup_hdr_offset; _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
