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
| ||
|
Message-ID: <18122.45437.807239.395869@cargo.ozlabs.ibm.com> Date: Tue, 21 Aug 2007 19:33:49 +1000 From: Paul Mackerras <paulus@...ba.org> To: Russell King <rmk+lkml@....linux.org.uk> Cc: Segher Boessenkool <segher@...nel.crashing.org>, Christoph Lameter <clameter@....com>, heiko.carstens@...ibm.com, horms@...ge.net.au, linux-kernel@...r.kernel.org, "Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>, ak@...e.de, netdev@...r.kernel.org, cfriesen@...tel.com, akpm@...ux-foundation.org, rpjday@...dspring.com, Nick Piggin <nickpiggin@...oo.com.au>, linux-arch@...r.kernel.org, jesper.juhl@...il.com, satyam@...radead.org, zlynx@....org, schwidefsky@...ibm.com, Chris Snook <csnook@...hat.com>, Herbert Xu <herbert@...dor.apana.org.au>, davem@...emloft.net, Linus Torvalds <torvalds@...ux-foundation.org>, wensong@...ux-vs.org, wjiang@...ilience.com Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures Russell King writes: > Let me say it more clearly: On ARM, it is impossible to perform atomic > operations on MMIO space. Actually, no one is suggesting that we try to do that at all. The discussion about RMW ops on MMIO space started with a comment attributed to the gcc developers that one reason why gcc on x86 doesn't use instructions that do RMW ops on volatile variables is that volatile is used to mark MMIO addresses, and there was some uncertainty about whether (non-atomic) RMW ops on x86 could be used on MMIO. This is in regard to the question about why gcc on x86 always moves a volatile variable into a register before doing anything to it. So the whole discussion is irrelevant to ARM, PowerPC and any other architecture except x86[-64]. Paul. - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists