Re: [PATCH 0/8] arm64/perf: Enable branch stack sampling

[Will Deacon]

On Mon, Jun 13, 2022 at 03:31:11PM +0530, Anshuman Khandual wrote:
> This series enables perf branch stack sampling support on arm64 platform
> via a new arch feature called Branch Record Buffer Extension (BRBE). All
> relevant register definitions could be accessed here.
> 
> https://developer.arm.com/documentation/ddi0601/2021-12/AArch64-Registers
> 
> This series applies on v5.19-rc2 after the BRBE related perf ABI changes series
> (V6) that was posted earlier.
> 
> https://lore.kernel.org/linux-arm-kernel/20220610035101.424112-1-anshuman.khandual@xxxxxxx/
> 
> Following issues remain inconclusive
> 
> - Jame's concerns regarding permission inadequacy related to perfmon_capable()
> - Jame's concerns regarding using perf_event_paranoid along with perfmon_capable()

afaict, the capability stuff remains unresolved with the SPE driver, so I'd
really like to see it fixed there first before we add more broken drivers.

https://lore.kernel.org/r/20220118100702.GB16547@willie-the-truck

Will