On 07/17/2018 12:40 PM, Peter Maydell wrote: > On 17 July 2018 at 18:29, Richard Henderson > <richard.hender...@linaro.org> wrote: >> I don't understand why this is necessary in the v8m case. >> >> AP APL >> <----B1----|----L1-B2-A-------|---L2---> >> >> >> Your comment posits two regions [B1,L1] and [B2,L2], that A is not within >> [B1,L1] but is within [B2,L2] (otherwise we would not report a hit at all). >> Further, that [B1,L1] intersects [AP,APL] but does not intersect [B2,L2] >> (otherwise we would report a fault for overlapping regions). >> >> Surely this combination of ranges implies that [B2,L2] must itself set >> IS_SUBPAGE (otherwise the first region would not overlap the page of A, or >> would not overlap the second region). > > (a) the overlap fault is only for addresses which are actually in the > overlap (ie "you asked about address X and it hits in R1 and R2"); it > doesn't imply that other addresses which are only in R1 fault just > because some part of R1 overlaps with R2.
Ah, that wasn't clear from the manual. > So for instance: > > AP APL > [B1 L1] > [B2 L2] > A1^ A2^ Thanks for the example, Reviewed-by: Richard Henderson <richard.hender...@linaro.org> r~
