On Tue, Mar 23, 2010 at 02:04:03AM +0100, Ralf Baechle 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%. > > I've just committed a patch on the master branch to handle this issue. > On cores that are not affected by the M3 bug this also fixes the module > issue. I've committed two more patches to fix the M3 errata handler. I don't have hardware affected by this CPU bug so I had to test the code with a little hack on another system. So tests on Swarm boards, especially with SOC versions older than C0 would be appreciated. After I receive positive feedback I will cherrypick the fixes into the stable branches. Ralf
