Hi Pratyush,
On 10/24/16 at 10:18pm, Pratyush Anand wrote:
> Patch 1/4 fixes page_offset calculation, so that it is correctly calculated
> on KASLR enabled kernel as well.
> Patch 2/4 simplifies VA to PA translation. New code has been benchmarked
> against old code on a 4T system.
> Patch 3/4 and 4/4 is removal of (now) unnecessary code.
>
> I think, we should find a way to kill find_vememmap() as well, so that
> VMEMMAP_START can be removed. I have very limited idea about x86, so unable
> to do that as of now.
>
> Pratyush Anand (4):
> x86_64: Calculate page_offset from pt_load
> x86_64: translate all VA to PA using page table values
> x86_64: kill is_vmalloc_addr_x86_64()
> x86_64: kill some unused initialization
>
> arch/x86_64.c | 84 ++++++++++++++++++++--------------------------------------
> makedumpfile.h | 9 +++----
> 2 files changed, 32 insertions(+), 61 deletions(-)
>
According to our test, with these patches the dumped vmcore is correct
which means simple crash test `bt` works. But the saved vmcore size is
larger than before.
I collected two --message-level 31 logs with/without your patches, the
kernel kaslr was disabled during my test so that we can focus on the
vmcore size issue, it looks like mem_map address was not collected
correctly.
[please ignore the patched log extra debug message I added]
--- unpatched-makedumpfile.txt 2016-10-27 10:31:34.152962407 +0800
+++ patched-makedumpfile.txt 2016-10-27 10:28:44.213952179 +0800
@@ -1,4 +1,4 @@
-[127.0.0.1-2016-10-27-10:27:03]# /tmp/makedumpfile -l -d 31 --message-level 31 vmcore vmcore.m.1
+[127.0.0.1-2016-10-27-10:27:03]# /home/dyoung/git/makedumpfile/makedumpfile -l -d 31 --message-level 31 vmcore vmcore.m
sadump: does not have partition header
sadump: read dump device as unknown format
sadump: unknown format
@@ -36,70 +36,76 @@
Memory type : SPARSEMEM_EX
+printing memmap .....
mem_map (0)
- mem_map : ffffea0000000000
+ mem_map : 0
pfn_start : 0
pfn_end : 8000
+printing memmap .....
mem_map (1)
- mem_map : ffffea0000200000
+ mem_map : 0
pfn_start : 8000
pfn_end : 10000
+printing memmap .....
mem_map (2)
- mem_map : ffffea0000400000
+ mem_map : 0
pfn_start : 10000
pfn_end : 18000
+printing memmap .....
mem_map (3)
- mem_map : ffffea0000600000
+ mem_map : 0
pfn_start : 18000
pfn_end : 20000
+printing memmap .....
mem_map (4)
- mem_map : ffffea0000800000
+ mem_map : 0
pfn_start : 20000
pfn_end : 28000
+printing memmap .....
mem_map (5)
- mem_map : ffffea0000a00000
+ mem_map : 0
pfn_start : 28000
pfn_end : 30000
+printing memmap .....
mem_map (6)
- mem_map : ffffea0000c00000
+ mem_map : 0
pfn_start : 30000
pfn_end : 38000
+printing memmap .....
mem_map (7)
- mem_map : ffffea0000e00000
+ mem_map : 0
pfn_start : 38000
pfn_end : 3ffda
mmap() is available on the kernel.
Checking for memory holes : [100.0 %] |STEP [Checking for memory holes ] : 0.000030 seconds
-Excluding unnecessary pages : [100.0 %] \STEP [Excluding unnecessary pages] : 0.007547 seconds
-Checking for memory holes : [100.0 %] -STEP [Checking for memory holes ] : 0.000016 seconds
-Checking for memory holes : [100.0 %] /STEP [Checking for memory holes ] : 0.000009 seconds
-Excluding unnecessary pages : [100.0 %] |STEP [Excluding unnecessary pages] : 0.006623 seconds
-Copying data : [100.0 %] \STEP [Copying data ] : 0.184442 seconds
-Copying data : [100.0 %] -STEP [Copying data ] : 0.000041 seconds
+Excluding unnecessary pages : [100.0 %] \STEP [Excluding unnecessary pages] : 0.000007 seconds
+Checking for memory holes : [100.0 %] -STEP [Checking for memory holes ] : 0.000014 seconds
+Checking for memory holes : [100.0 %] /STEP [Checking for memory holes ] : 0.000008 seconds
+Excluding unnecessary pages : [100.0 %] |STEP [Excluding unnecessary pages] : 0.000007 seconds
+Copying data : [100.0 %] /STEP [Copying data ] : 1.421661 seconds
+Copying data : [100.0 %] |STEP [Copying data ] : 0.000036 seconds
Writing erase info...
-offset_eraseinfo: dd5c4e, size_eraseinfo: 0
+offset_eraseinfo: 888c149, size_eraseinfo: 0
Original pages : 0x0000000000030c7d
- Excluded pages : 0x000000000002cf58
- Pages filled with zero : 0x00000000000002be
- Non-private cache pages : 0x0000000000006574
- Private cache pages : 0x0000000000000f27
- User process data pages : 0x0000000000003481
- Free pages : 0x000000000002237e
+ Excluded pages : 0x000000000001d534
+ Pages filled with zero : 0x000000000001d534
+ Non-private cache pages : 0x0000000000000000
+ Private cache pages : 0x0000000000000000
+ User process data pages : 0x0000000000000000
+ Free pages : 0x0000000000000000
Hwpoison pages : 0x0000000000000000
- Remaining pages : 0x0000000000003d25
- (The number of pages is reduced to 7%.)
+ Remaining pages : 0x0000000000013749
+ (The number of pages is reduced to 39%.)
Memory Hole : 0x000000000000f35d
--------------------------------------------------
Total pages : 0x000000000003ffda
-Cache hit: 29946, miss: 47, hit rate: 99.8%
+Cache hit: 196285, miss: 201, hit rate: 99.9%
-The dumpfile is saved to vmcore.m.1.
+The dumpfile is saved to vmcore.m.
makedumpfile Completed.
-[root at dhcp-128-65 127.0.0.1-2016-10-27-10:27:03]# ls -lth vmcore.m*
--rw------- 1 root root 14M Oct 27 10:30 vmcore.m.1
--rw------- 1 root root 137M Oct 27 10:28 vmcore.m
+[root at dhcp-128-65 127.0.0.1-2016-10-27-10:27:03]#
