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From: Ravi Bangoria <ravi.bangoria@amd.com>
To: "Mi, Dapeng" <dapeng1.mi@linux.intel.com>,
	Namhyung Kim <namhyung@kernel.org>
Cc: Gennady Kupava <gennady.kupava@gmail.com>,
	<linux-perf-users@vger.kernel.org>,
	Ravi Bangoria <ravi.bangoria@amd.com>
Subject: Re: [DISCUSSION] Three problems behind broken "perf --call-graph dwarf" on AMD: IP and stack dump mismatch, libdw fails on lld's layout, and the unwinder fallback never runs
Date: Thu, 3 Sep 2026 21:32:49 +0530	[thread overview]
Message-ID: <0e5e1fd0-0a46-4c1c-a391-5c245d903834@amd.com> (raw)
In-Reply-To: <a5d3798c-7d62-43d0-88c6-eec26bd4f63d@linux.intel.com>

> Suppose we need to follow below 2 rules to ensure the correct call-chain
> unwinding and register snapshot consistency.
> 
> 1. All registers including IP should come from either PEBS or PMI, must not
> be mixed. This ensures to get an consistent registers snapshot.
> 
> 2. Either SAMPLE_CALLCHAIN or SAMPLE_STACK_USER is required, the PMI
> registers snapshot must be used. This proves the correct DWARF unwinding.
> 
> How's your idea?

Looks good. Mind sending the patch?

Thanks,
Ravi

  reply	other threads:[~2026-09-03 16:04 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-21 21:49 [DISCUSSION] Three problems behind broken "perf --call-graph dwarf" on AMD: IP and stack dump mismatch, libdw fails on lld's layout, and the unwinder fallback never runs Gennady Kupava
2026-08-24 13:35 ` Ravi Bangoria
2026-08-25 18:05 ` Ian Rogers
2026-08-27 21:55 ` Namhyung Kim
2026-08-28 16:47   ` Namhyung Kim
2026-08-28 16:58   ` Namhyung Kim
2026-08-31  5:05     ` Ravi Bangoria
2026-09-01 15:19       ` Namhyung Kim
2026-09-03  8:39         ` Mi, Dapeng
2026-09-03 11:36           ` Ravi Bangoria
2026-09-03 11:59             ` Mi, Dapeng
2026-09-03 16:02               ` Ravi Bangoria [this message]
2026-09-04  0:22                 ` Mi, Dapeng
2026-09-05 10:14                   ` Gennady Kupava

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