powerpc/fadump: use the correct VMCOREINFO_NOTE_SIZE for phdr

vmcoreinfo_max_size stands for the vmcoreinfo_data, the correct one we
should use is vmcoreinfo_note whose total size is VMCOREINFO_NOTE_SIZE.

Like explained in commit 77019967f06b ("kdump: fix exported size of
vmcoreinfo note"), it should not affect the actual function, but we
better fix it, also this change should be safe and backward compatible.

After this, we can get rid of variable vmcoreinfo_max_size, let's use
the corresponding macros directly, fewer variables means more safety for
vmcoreinfo operation.

[xlpang@redhat.com: fix build warning]
Link: http://lkml.kernel.org/r/1494830606-27736-1-git-send-email-xlpang@redhat.com
Link: http://lkml.kernel.org/r/1493281021-20737-2-git-send-email-xlpang@redhat.com
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reviewed-by: Dave Young <dyoung@redhat.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 3079518f2245c98f80efe3c9cd96952f2cc78d69..dc0c49cfd90a093aba02fc3f8931e87d687380a7 100644 (file)
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -999,8 +999,7 @@ static int fadump_create_elfcore_headers(char *bufp)
 
        phdr->p_paddr   = fadump_relocate(paddr_vmcoreinfo_note());
        phdr->p_offset  = phdr->p_paddr;
-       phdr->p_memsz   = vmcoreinfo_max_size;
-       phdr->p_filesz  = vmcoreinfo_max_size;
+       phdr->p_memsz   = phdr->p_filesz = VMCOREINFO_NOTE_SIZE;
 
        /* Increment number of program headers. */
        (elf->e_phnum)++;

diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h
index 87506a02e9140888ce2382469a326a14eb42106c..e5df1b3cf072633f2b0a37becdbaa849b2d07871 100644 (file)
--- a/include/linux/crash_core.h
+++ b/include/linux/crash_core.h
@@ -58,7 +58,6 @@ phys_addr_t paddr_vmcoreinfo_note(void);
 
 extern u32 *vmcoreinfo_note;
 extern size_t vmcoreinfo_size;
-extern size_t vmcoreinfo_max_size;
 
 Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type,
                          void *data, size_t data_len);

diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index 2837d6164db8139ed48d35fb9784e6df59c1e1b9..315adbf9cb680b7efc28875d8e50c7ff617cfd6d 100644 (file)
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -16,7 +16,6 @@
 /* vmcoreinfo stuff */
 static unsigned char *vmcoreinfo_data;
 size_t vmcoreinfo_size;
-size_t vmcoreinfo_max_size = VMCOREINFO_BYTES;
 u32 *vmcoreinfo_note;
 
 /*
@@ -343,7 +342,7 @@ void vmcoreinfo_append_str(const char *fmt, ...)
        r = vscnprintf(buf, sizeof(buf), fmt, args);
        va_end(args);
 
-       r = min(r, vmcoreinfo_max_size - vmcoreinfo_size);
+       r = min(r, (size_t)VMCOREINFO_BYTES - vmcoreinfo_size);
 
        memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);