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Donenfeld" , "Gustavo A. R. Silva" , "Mark Rutland" , "Steven Rostedt" , "Mark Brown" , "Guo Hui" , Manoj.Iyer@arm.com, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, "James Yang" , "Shiyou Huang" Subject: Re: [PATCH 1/1] arm64: syscall: Direct PRNG kstack randomization X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240308_123017_861234_5E2BCAAF X-CRM114-Status: UNSURE ( 8.56 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Mar 8, 2024, at 17:49, Jeremy Linton wrote: > On 3/7/24 05:10, Arnd Bergmann wrote: >> >> I'm not sure I understand the logic. Do you mean that accessing >> CNTVCT itself is slow, or that reseeding based on CNTVCT is slow >> because of the overhead of reseeding? > > Slow, as in, its running at a much lower frequency than a cycle counter. Ok, I see. Would it be possible to use PMEVCNTR0 instead? Arnd _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel