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| author |   Hari Bathini <hbathini@linux.vnet.ibm.com> | 2017-06-01 22:50:38 +0530 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2017-06-28 13:08:09 +1000 |
| commit | a77af552ccc9d4d54459a39f9e5f7ad307aeb4f9 (patch) | |
| tree | 38828bbf06699dc522a53bda498dd8b1a43bbd39 /arch/powerpc/kernel/fadump.c | |
| parent | powerpc/perf: Fix branch event code for power9 (diff) | |
| download | linux-dev-a77af552ccc9d4d54459a39f9e5f7ad307aeb4f9.tar.xz linux-dev-a77af552ccc9d4d54459a39f9e5f7ad307aeb4f9.zip | |
powerpc/fadump: avoid duplicates in crash memory ranges
fadump sets up crash memory ranges to be used for creating PT_LOAD
program headers in elfcore header. Memory chunk RMA_START through
boot memory area size is added as the first memory range because
firmware, at the time of crash, moves this memory chunk to different
location specified during fadump registration making it necessary to
create a separate program header for it with the correct offset.
This memory chunk is skipped while setting up the remaining memory
ranges. But currently, there is possibility that some of this memory
may have duplicate entries like when it is hot-removed and added
again. Ensure that no two memory ranges represent the same memory.
When 5 lmbs are hot-removed and then hot-plugged before registering
fadump, here is how the program headers in /proc/vmcore exported by
fadump look like
without this change:
Program Headers:
Type Offset VirtAddr PhysAddr
FileSiz MemSiz Flags Align
NOTE 0x0000000000010000 0x0000000000000000 0x0000000000000000
0x0000000000001894 0x0000000000001894 0
LOAD 0x0000000000021020 0xc000000000000000 0x0000000000000000
0x0000000040000000 0x0000000040000000 RWE 0
LOAD 0x0000000040031020 0xc000000000000000 0x0000000000000000
0x0000000010000000 0x0000000010000000 RWE 0
LOAD 0x0000000050040000 0xc000000010000000 0x0000000010000000
0x0000000050000000 0x0000000050000000 RWE 0
LOAD 0x00000000a0040000 0xc000000060000000 0x0000000060000000
0x000000019ffe0000 0x000000019ffe0000 RWE 0
and with this change:
Program Headers:
Type Offset VirtAddr PhysAddr
FileSiz MemSiz Flags Align
NOTE 0x0000000000010000 0x0000000000000000 0x0000000000000000
0x0000000000001894 0x0000000000001894 0
LOAD 0x0000000000021020 0xc000000000000000 0x0000000000000000
0x0000000040000000 0x0000000040000000 RWE 0
LOAD 0x0000000040030000 0xc000000040000000 0x0000000040000000
0x0000000020000000 0x0000000020000000 RWE 0
LOAD 0x0000000060030000 0xc000000060000000 0x0000000060000000
0x000000019ffe0000 0x000000019ffe0000 RWE 0
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Reviewed-by: Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel/fadump.c')
| -rw-r--r-- | arch/powerpc/kernel/fadump.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c index 12837d52e84a..08e00448a355 100644 --- a/arch/powerpc/kernel/fadump.c +++ b/arch/powerpc/kernel/fadump.c @@ -878,8 +878,19 @@ static void fadump_setup_crash_memory_ranges(void) for_each_memblock(memory, reg) { start = (unsigned long long)reg->base; end = start + (unsigned long long)reg->size; - if (start == RMA_START && end >= fw_dump.boot_memory_size) - start = fw_dump.boot_memory_size; + + /* + * skip the first memory chunk that is already added (RMA_START + * through boot_memory_size). This logic needs a relook if and + * when RMA_START changes to a non-zero value. + */ + BUILD_BUG_ON(RMA_START != 0); + if (start < fw_dump.boot_memory_size) { + if (end > fw_dump.boot_memory_size) + start = fw_dump.boot_memory_size; + else + continue; + } /* add this range excluding the reserved dump area. */ fadump_exclude_reserved_area(start, end); |