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charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu On Wednesday 28 Jul 2021 at 15:32:32 (+0000), David Brazdil wrote: > Currently range_is_memory finds the corresponding struct memblock_region > for both the lower and upper bounds of the given address range with two > rounds of binary search, and then checks that the two memblocks are the > same. Simplify this by only doing binary search on the lower bound and > then checking that the upper bound is in the same memblock. > > Signed-off-by: David Brazdil > --- > arch/arm64/kvm/hyp/nvhe/mem_protect.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c > index a6ce991b1467..37d73af69634 100644 > --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c > +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c > @@ -189,13 +189,18 @@ static bool find_mem_range(phys_addr_t addr, struct kvm_mem_range *range) > return false; > } > > +static bool is_in_mem_range(phys_addr_t addr, struct kvm_mem_range *range) > +{ Nit: addr@ could be u64 for consistency -- struct kvm_mem_range holds IPAs in general. > + return range->start <= addr && addr < range->end; > +} > + > static bool range_is_memory(u64 start, u64 end) > { > - struct kvm_mem_range r1, r2; > + struct kvm_mem_range r; > > - if (!find_mem_range(start, &r1) || !find_mem_range(end - 1, &r2)) > + if (!find_mem_range(start, &r)) > return false; > - if (r1.start != r2.start) > + if (!is_in_mem_range(end - 1, &r)) > return false; > > return true; Nit: maybe drop the second if and simplify to: return is_in_mem_range(end - 1, &r); With that: Reviewed-by: Quentin Perret Thanks, Quentin _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm