diff options
author | Sean Christopherson <[email protected]> | 2018-12-04 13:25:57 -0800 |
---|---|---|
committer | Ingo Molnar <[email protected]> | 2018-12-05 08:58:11 +0100 |
commit | 24b7c77bbb24f129beead93574ff248c3db1288e (patch) | |
tree | f6838fb2e81c4c0498b5452db0a2fdbc1dca341f /tools/perf/util/scripting-engines/trace-event-python.c | |
parent | 566b62a3676caed1f8c626e26066ff3ae3a38918 (diff) |
x86/vdso: Remove obsolete "fake section table" reservation
At one point the vDSO image was manually stripped down by vdso2c in an
attempt to minimize the size of the image mapped into userspace. Part
of that stripping process involved building a fake section table so as
not to break userspace processes that parse the section table. Memory
for the fake section table was reserved in the .rodata section so that
vdso2c could simply copy the entire PT_LOAD segment into the userspace
image after building the fake table.
Eventually, the entire fake section table approach was dropped in favor
of stripping the vdso "the old fashioned way", i.e. via objdump -S.
But, the reservation in .rodata for the fake table was left behind.
Remove the reserveration along with a few other related defines and
section entries.
Removing the fake section table placeholder zaps a whopping 0x340 bytes
from the 64-bit vDSO image, which drops the current image's size to
under 4k, i.e. reduces the effective size of the userspace vDSO mapping
by a full page.
Signed-off-by: Sean Christopherson <[email protected]>
Acked-by: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Fixes: da861e18eccc ("x86, vdso: Get rid of the fake section mechanism")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
Diffstat (limited to 'tools/perf/util/scripting-engines/trace-event-python.c')
0 files changed, 0 insertions, 0 deletions