Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20230602123815.255001-1-paniii94@gmail.com>
In-Reply-To: <20230602123815.255001-1-paniii94@gmail.com>
From:   Namhyung Kim <namhyung@kernel.org>
Date:   Wed, 21 Jun 2023 10:21:58 -0700
Message-ID: <CAM9d7ciXeG=9qhZ-5qs=ZR=iEmYD64OVjhd+z+wh_TPjsWaaEA@mail.gmail.com>
Subject: Re: [PATCH v2] Subject: perf jit: Fix incorrect file name in DWARF
 line table
To:     Elisabeth <paniii94@gmail.com>
Cc:     Elisabeth Panholzer <elisabeth@leaningtech.com>,
        linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8BIT
Precedence: bulk

On Fri, Jun 2, 2023 at 5:38 AM Elisabeth <paniii94@gmail.com> wrote:
>
> From: elisabeth <paniii94@gmail.com>
>
> Fixes an issue where an incorrect filename was added in the DWARF line table of
> an ELF object file when calling 'perf inject --jit' due to not checking the
> filename of a debug entry against the repeated name marker (/xff/0).
> The marker is mentioned in the tools/perf/util/jitdump.h header, which describes
> the jitdump binary format, and indicitates that the filename in a debug entry
> is the same as the previous enrty.
> In the function emit_lineno_info(), in the file tools/perf/util/genelf-debug.c,
> the debug entry filename gets compared to the previous entry filename. If they
> are not the same, a new filename is added to the DWARF line table. However,
> since there is no check against '\xff\0', in some cases '\xff\0' is inserted
> as the filename into the DWARF line table.
> This can be seen with `objdump --dwarf=line` on the ELF file after `perf inject --jit`.
> It also makes no source code information show up in 'perf annotate'.
>
> Signed-off-by: Elisabeth Panholzer <elisabeth@leaningtech.com>
> Cc: linux-kernel@vger.kernel.org
> Cc: linux-perf-users@vger.kernel.org

Applied to perf-tools-next, thanks!