Re: [GIT PULL] siginfo: ABI fixes for v5.13-rc2

From: Eric W. Biederman
Date: Mon May 17 2021 - 11:45:48 EST


Ingo Molnar <mingo@xxxxxxxxxx> writes:

> * Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote:
>
>> Looking deeper it was discovered that si_trapno is used for only
>> a few select signals on alpha and sparc, and that none of the
>> other _sigfault fields past si_addr are used at all. Which means
>> technically no regression on alpha and sparc.
>
> If there's no functional regression on any platform, could much of this
> wait until v5.14, or do we want some of these cleanups right now?
>
> The fixes seem to be for long-existing bugs, not fresh regressions, AFAICS.
> The asserts & cleanups are useful, but not regression fixes.
>
> I.e. this is a bit scary:

The new ABI for SIGTRAP TRAP perf that came in the merge window is
broken and wrong. We need to revert/disable the new SIGTRAP TRAP_PERF
or have a fix before v5.13.

The issue is old crap getting in the way of a new addition. I think I
might see a smaller code change on how to get to something compatible
with this.

>> 32 files changed, 377 insertions(+), 163 deletions(-)
>
> at -rc2 time.

The additions are all tests to make certain everything is fine.
The actual code change without the assertions (tests) is essentially
a wash.

Eric