[tip: x86/urgent] kexec_file: Correctly output debugging information for the PT_LOAD ELF header
From: tip-bot2 for Lianbo Jiang
Date: Thu Aug 06 2020 - 13:11:57 EST
The following commit has been merged into the x86/urgent branch of tip:
Commit-ID: 8ca346039f70cf92dbada6c06048efde165b191f
Gitweb: https://git.kernel.org/tip/8ca346039f70cf92dbada6c06048efde165b191f
Author: Lianbo Jiang <lijiang@xxxxxxxxxx>
AuthorDate: Tue, 04 Aug 2020 12:49:33 +08:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Thu, 06 Aug 2020 15:26:09 +02:00
kexec_file: Correctly output debugging information for the PT_LOAD ELF header
Currently, when we enable the debugging switch to debug kexec_file,
we always get the following incorrect results:
kexec_file: Crash PT_LOAD elf header. phdr=00000000c988639b vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=51 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=000000003cca69a0 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=52 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=00000000c584cb9f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=53 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=00000000cf85d57f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=54 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=00000000a4a8f847 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=55 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=00000000272ec49f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=56 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=00000000ea0b65de vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=57 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=000000001f5e490c vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=58 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=00000000dfe4109e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=59 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=00000000480ed2b6 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=60 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=0000000080b65151 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=61 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=0000000024e31c5e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=62 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=00000000332e0385 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=63 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=000000002754d5da vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=64 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=00000000783320dd vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=65 p_offset=0x0
kexec_file: Crash PT_LOAD elf header. phdr=0000000076fe5b64 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=66 p_offset=0x0
The reason is that kernel always prints the values of the next PT_LOAD
instead of the current PT_LOAD. Change it to ensure that we can get the
correct debugging information.
[ mingo: Amended changelog, capitalized "ELF". ]
Signed-off-by: Lianbo Jiang <lijiang@xxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Acked-by: Dave Young <dyoung@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20200804044933.1973-4-lijiang@xxxxxxxxxx
---
kernel/kexec_file.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 5cc2c47..f1f4009 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -1246,7 +1246,7 @@ int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
unsigned long long notes_addr;
unsigned long mstart, mend;
- /* extra phdr for vmcoreinfo elf note */
+ /* extra phdr for vmcoreinfo ELF note */
nr_phdr = nr_cpus + 1;
nr_phdr += mem->nr_ranges;
@@ -1254,7 +1254,7 @@ int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
* kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
* area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64).
* I think this is required by tools like gdb. So same physical
- * memory will be mapped in two elf headers. One will contain kernel
+ * memory will be mapped in two ELF headers. One will contain kernel
* text virtual addresses and other will have __va(physical) addresses.
*/
@@ -1323,10 +1323,10 @@ int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
phdr->p_align = 0;
ehdr->e_phnum++;
- phdr++;
- pr_debug("Crash PT_LOAD elf header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n",
+ pr_debug("Crash PT_LOAD ELF header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n",
phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
ehdr->e_phnum, phdr->p_offset);
+ phdr++;
}
*addr = buf;