kernel/linux.git/include/linux/instruction_pointer.h, branch v6.19.11Linux kernel stable tree (mirror)https://git.radix-linux.su/kernel/linux.git/atom?h=v6.19.112023-09-12T15:50:53+00:00x86/ibt: Suppress spurious ENDBR2023-09-12T15:50:53+00:00Peter Zijlstrapeterz@infradead.org2023-08-02T10:55:46+00:00urn:sha1:25e73b7e3f72a25aa30cbb2eecb49036e0acf066
It was reported that under certain circumstances GCC emits ENDBR
instructions for _THIS_IP_ usage. Specifically, when it appears at the
start of a basic block -- but not elsewhere.
Since _THIS_IP_ is never used for control flow, these ENDBR
instructions are completely superfluous. Override the _THIS_IP_
definition for x86_64 to avoid this.
Less ENDBR instructions is better.
Fixes: 156ff4a544ae ("x86/ibt: Base IBT bits")
Reported-by: David Kaplan <David.Kaplan@amd.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230802110323.016197440@infradead.org
kernel.h: split out instruction pointer accessors2021-11-09T18:02:49+00:00Stephen Rothwellsfr@canb.auug.org.au2021-11-09T02:32:43+00:00urn:sha1:e52340de11d8bca3ba35e5a72fea4f2a5b6abbbb
bottom_half.h needs _THIS_IP_ to be standalone, so split that and
_RET_IP_ out from kernel.h into the new instruction_pointer.h. kernel.h
directly needs them, so include it there and replace the include of
kernel.h with this new file in bottom_half.h.
Link: https://lkml.kernel.org/r/20211028161248.45232-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>