On Sun, Mar 21, 2010 at 12:02:41PM +0100, Sebastian Andrzej Siewior wrote: > Since commit 656be92f aka "Load modules to CKSEG0 if > CONFIG_BUILD_ELF64=n" module support is broken on 64bit. Since then > modules arr loaded into 32bit compat adresses which are sign extended > 64bit addresses. The SiByte war handler was not updated and those > addresses were not recognized by the TLB hadling. > This patch fixes this by shifting away the upper bits including the R > and Fill bits. Now we compare VPN2 of C0_ENTRYHI against the matching > bits at C0_BADVADDR. Good detective work but I'll check against the errata documents (which are non-public, sigh ...) before applying your patch. The M3 workaround in which you found this bug is currently applied to all Sibyte SB1 cores while probably only a relativly small number of the cores in circulation are affected so we should refine the workaround to be only applied if the System Revision Register indicates a system older than revision C0. This could get rid of 6 instructions which according to the usual rule of thumb would result in a speedup of ~ 3%. Ralf
