linux-kernel - Re: [PATCH] perf/x86/intel: Fix unwind errors from PEBS entries (mk-II)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAJAFBLDtRUwYhMaOrgHer4eTvjWL2jC-fy0GGv+Pjd8q3wgywA@mail.gmail.com>
Date:   Mon, 6 Aug 2018 08:35:07 -0700
From:   Fubo Chen <fubo.chen@...il.com>
To:     peterz@...radead.org
Cc:     jpoimboe@...hat.com, Ingo Molnar <mingo@...nel.org>,
        bhole_prashant_q7@....ntt.co.jp,
        Linux Kernel <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] perf/x86/intel: Fix unwind errors from PEBS entries (mk-II)

On Thu, Jul 19, 2018 at 2:21 PM Peter Zijlstra <peterz@...radead.org> wrote:
> --- a/include/uapi/linux/perf_event.h
> +++ b/include/uapi/linux/perf_event.h
> @@ -143,6 +143,8 @@ enum perf_event_sample_format {
>         PERF_SAMPLE_PHYS_ADDR                   = 1U << 19,
>
>         PERF_SAMPLE_MAX = 1U << 20,             /* non-ABI */
> +
> +       __PERF_SAMPLE_CALLCHAIN_EARLY           = 1UL << 63,
>  };

The above change makes sparse unhappy :-( Sparse reports the following
complaint about __PERF_SAMPLE_CALLCHAIN_EARLY:

./include/uapi/linux/perf_event.h:147:56: warning: cast truncates bits
from constant value (8000000000000000 becomes 0)

Is the above change portable? Isn't a compiler allowed to use 'int' to
represent an enumeration type?

Fubo.