path: root/mm
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authorPingfan Liu <>2021-06-15 18:23:36 -0700
committerLinus Torvalds <>2021-06-16 09:24:42 -0700
commit4f5aecdff25f59fb5ea456d5152a913906ecf287 (patch)
tree43418f95b8c986b302faa5f94437c7afd081ccf2 /mm
parente8675d291ac007e1c636870db880f837a9ea112a (diff)
crash_core, vmcoreinfo: append 'SECTION_SIZE_BITS' to vmcoreinfo
As mentioned in kernel commit 1d50e5d0c505 ("crash_core, vmcoreinfo: Append 'MAX_PHYSMEM_BITS' to vmcoreinfo"), SECTION_SIZE_BITS in the formula: #define SECTIONS_SHIFT (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS) Besides SECTIONS_SHIFT, SECTION_SIZE_BITS is also used to calculate PAGES_PER_SECTION in makedumpfile just like kernel. Unfortunately, this arch-dependent macro SECTION_SIZE_BITS changes, e.g. recently in kernel commit f0b13ee23241 ("arm64/sparsemem: reduce SECTION_SIZE_BITS"). But user space wants a stable interface to get this info. Such info is impossible to be deduced from a crashdump vmcore. Hence append SECTION_SIZE_BITS to vmcoreinfo. Link: Link: Signed-off-by: Pingfan Liu <> Acked-by: Baoquan He <> Cc: Bhupesh Sharma <> Cc: Kazuhito Hagio <> Cc: Dave Young <> Cc: Boris Petkov <> Cc: Ingo Molnar <> Cc: Thomas Gleixner <> Cc: James Morse <> Cc: Mark Rutland <> Cc: Will Deacon <> Cc: Catalin Marinas <> Cc: Michael Ellerman <> Cc: Paul Mackerras <> Cc: Benjamin Herrenschmidt <> Cc: Dave Anderson <> Cc: <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'mm')
0 files changed, 0 insertions, 0 deletions