Re: [RHEL6.8 Patch 00/19] Support mmap() on /proc/vmcore

[Baoquan He <bhe@redhat.com>]

Sorry to bother you. I just sent to the wrong mailing list. Please
ignore this thread.

On 07/16/15 at 04:46pm, Baoquan He wrote:
> This patchset includes 3 parts.
> 
> -------------------------------------
> 1st part:
> Includes 13 upstream commits. They are recommended by Nigel Croxon
> since he back ported this feature to rhel7. This 13 back ports
> works for all ARCHs except of s390 since it always broke s390n kdump.
> 
> c2c1b08 fs/proc/vmcore.c: put if tests in the top of the while loop to reduce duplication
> 0fa73b8 include/linux/mm.h: add PAGE_ALIGNED() helper
> b27eb18 vmcore: clean up read_vmcore()
> f2bdacd vmcore: allocate buffer for ELF headers on page-size alignment
> 7f614cd vmcore: treat memory chunks referenced by PT_LOAD program header entries in page-size boundary in vmcore_list
> cef2ac3 vmalloc: make find_vm_area check in range
> e69e9d4a vmalloc: introduce remap_vmalloc_range_partial
> 087350c vmcore: allocate ELF note segment in the 2nd kernel vmalloc memory
> ef9e78f vmcore: allow user process to remap ELF note segment buffer
> 591ff71 vmcore: calculate vmcore file size from buffer size and total size of vmcore objects
> 8308697 vmcore: support mmap() on /proc/vmcore
> 5a74953 s390/kdump: Disable mmap for s390
> 0692ded fs/proc/vmcore.c:mmap_vmcore: skip non-ram pages reported by hypervisors
> 
> -------------------------------------
> 2nd part:
> Includes several s390 related memory commits. Since these 13 commits
> in 1st part worked on all ARCHs except of S390. Then I asked IBM
> S390 kernel developers Michael Holzheu <michael.holzheu@de.ibm.com>,
> Jan Willeke <WILLEKE@de.ibm.com> to help, they suggested these 3 commits.
> With them it works for s390 kdump.
> 
> 191a2fa s390/kdump: Allow copy_oldmem_page() copy to virtual memory"
> 9cb2181 vmcore: introduce remap_oldmem_pfn_range()"
> 23df79d s390/vmcore: implement remap_oldmem_pfn_range for s390"
> 
> -------------------------------------
> 3rd part:
> Includes 3 commits. They are back ported because 3 commits in
> 2nd part will fail x86 and ppc compiling.
> 
> 997c136 fs/proc/vmcore.c: add hook to read_from_oldmem() to check for non-ram pages
> 816422a asm-generic, mm: pgtable: consolidate zero page helpers
> 238ec4e [S390] zero page cache synonyms
> 
> 
> Brew build:
> 
> I made a brew build here and tested it on s390 and x86 machine,
> both works.
> https://brewweb.devel.redhat.com/taskinfo?taskID=9357037
> 
> Then Nigel took patches from my rh-git and made a brew build as below.
> Lisa from HP took a test and confirmed this works on HP machines
> and it improved the dump as expected.
> https://brewweb.devel.redhat.com/taskinfo?taskID=9380805
> 
> My rh-git for this feature is here:
> git://git.engineering.redhat.com/users/bhe/rhel6/.git mmap-new
> 
> Baoquan He (19):
>   [S390] zero page cache synonyms
>   asm-generic, mm: pgtable: consolidate zero page helpers
>   fs/proc/vmcore.c: add hook to read_from_oldmem() to check for non-ram
>     pages
>   fs/proc/vmcore.c: put if tests in the top of the while loop to reduce
>     duplication
>   include/linux/mm.h: add PAGE_ALIGNED() helper
>   vmcore: clean up read_vmcore()
>   vmcore: allocate buffer for ELF headers on page-size alignment
>   vmcore: treat memory chunks referenced by PT_LOAD program header
>     entries in page-size boundary in vmcore_list
>   vmalloc: make find_vm_area check in range
>   vmalloc: introduce remap_vmalloc_range_partial
>   vmcore: allocate ELF note segment in the 2nd kernel vmalloc memory
>   vmcore: allow user process to remap ELF note segment buffer
>   vmcore: calculate vmcore file size from buffer size and total size of
>     vmcore objects
>   vmcore: support mmap() on /proc/vmcore
>   s390/kdump: Disable mmap for s390
>   s390/kdump: Allow copy_oldmem_page() copy to virtual memory
>   vmcore: introduce remap_oldmem_pfn_range()
>   s390/vmcore: implement remap_oldmem_pfn_range for s390
>   fs/proc/vmcore.c:mmap_vmcore: skip non-ram pages reported by
>     hypervisors
> 
>  arch/mips/include/asm/pgtable.h |  10 +-
>  arch/s390/include/asm/pgtable.h |  14 +-
>  arch/s390/kernel/crash_dump.c   |  75 +++-
>  arch/s390/mm/init.c             |  49 ++-
>  fs/proc/vmcore.c                | 899 ++++++++++++++++++++++++++++++----------
>  include/asm-generic/pgtable.h   |  26 ++
>  include/linux/crash_dump.h      |   9 +
>  include/linux/mm.h              |   3 +
>  include/linux/vmalloc.h         |   4 +
>  mm/memory.c                     |  14 -
>  mm/vmalloc.c                    |  70 +++-
>  11 files changed, 901 insertions(+), 272 deletions(-)
> 
> -- 
> 2.1.0
>