Hi Christoffer I ever sent out the v3 patch set with the single patch 1/2 [link] https://patchwork.kernel.org/patch/10413803/ Sorry,I ping-ed the wrong mail thread ;-).
Cheers, Jia On 6/8/2018 4:34 PM, Christoffer Dall Wrote: > On Fri, May 18, 2018 at 09:04:40PM +0800, Jia He wrote: >> >> >> On 5/18/2018 5:48 PM, Marc Zyngier Wrote: >>> On 18/05/18 10:27, Jia He wrote: >>>> If it passes addr=0x202920000,size=0xfe00 to unmap_stage2_range-> >>>> ...->unmap_stage2_ptes, unmap_stage2_ptes will get addr=0x202920000, >>>> end=0x20292fe00. After first while loop addr=0x202930000, end=0x20292fe00, >>>> then addr!=end. Thus it will touch another pages by put_pages() in the >>>> 2nd loop. >>>> >>>> This patch fixes it by hardening the break condition of while loop. >>>> >>>> Signed-off-by: jia...@hxt-semitech.com >>>> --- >>>> v2: newly added >>>> >>>> virt/kvm/arm/mmu.c | 2 +- >>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>> >>>> diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c >>>> index 8dac311..45cd040 100644 >>>> --- a/virt/kvm/arm/mmu.c >>>> +++ b/virt/kvm/arm/mmu.c >>>> @@ -217,7 +217,7 @@ static void unmap_stage2_ptes(struct kvm *kvm, pmd_t >>>> *pmd, >>>> >>>> put_page(virt_to_page(pte)); >>>> } >>>> - } while (pte++, addr += PAGE_SIZE, addr != end); >>>> + } while (pte++, addr += PAGE_SIZE, addr < end); >>>> >>>> if (stage2_pte_table_empty(start_pte)) >>>> clear_stage2_pmd_entry(kvm, pmd, start_addr); >>>> >>> >>> I don't think this change is the right thing to do. You get that failure >>> because you're being passed a size that is not a multiple of PAGE_SIZE. >>> That's the mistake. >>> >>> You should ensure that this never happens, rather than changing the page >>> table walkers (which are consistent with the way this kind of code is >>> written in other places of the kernel). As you mentioned in your first >>> patch, the real issue is that KSM is broken, and this is what should be >>> fixed. >>> >> Got it, thanks >> Should I resend the patch 1/2 without any changes after droping patch 2/2? >> > > That's fine if you trim the commit message to make it look nicer. > > Also, in the future, please include a cover letter if you send more than > one patch to the list. > > Thanks, > -Christoffer > _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
