Non-PAE 32-bit dump kernels may wrap an address around 4G and
poke unwanted space. ptes there are 32-bit long, and since
pfn << PAGE_SIZE may exceed this limit, high pfn bits are
cropped and wrong address mapped by kmap_atomic_pfn in
copy_oldmem_page.
Don't allow this behavior in non-PAE kdump kernels by checking
pfns passed into copy_oldmem_page. In the case of failure,
userspace process gets EFAULT.
[v2]
- fix comments
- move ifdefs inside the function
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Paul Mundt <lethal@linux-sh.org>
LKML-Reference: <1256551903-30567-1-git-send-email-jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
o elfcorehdr_addr is used by not only the code under CONFIG_PROC_VMCORE
but also by the code which is not inside CONFIG_PROC_VMCORE. For
example, is_kdump_kernel() is used by powerpc code to determine if
kernel is booting after a panic then use previous kernel's TCE table.
So even if CONFIG_PROC_VMCORE is not set in second kernel, one should be
able to correctly determine that we are booting after a panic and setup
calgary iommu accordingly.
o So remove the assumption that elfcorehdr_addr is under
CONFIG_PROC_VMCORE.
o Move definition of elfcorehdr_addr to arch dependent crash files.
(Unfortunately crash dump does not have an arch independent file
otherwise that would have been the best place).
o kexec.c is not the right place as one can Have CRASH_DUMP enabled in
second kernel without KEXEC being enabled.
o I don't see sh setup code parsing the command line for
elfcorehdr_addr. I am wondering how does vmcore interface work on sh.
Anyway, I am atleast defining elfcoredhr_addr so that compilation is not
broken on sh.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Simon Horman <horms@verge.net.au>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
copy_oldmem_page should not return leaving a page frame from the
previous kernel mapped.
Signed-off-by: Fernando Luis Vázquez Cao <fernando@oss.ntt.co.jp>
Acked-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since the x86 merge, lots of files that referenced their own filenames
are no longer correct. Rather than keep them up to date, just delete
them, as they add no real value.
Additionally:
- fix up comment formatting in scx200_32.c
- Remove a credit from myself in setup_64.c from a time when we had no SCM
- remove longwinded history from tsc_32.c which can be figured out from
git.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
