Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Thu, 3 Mar 2022 12:19:33 +0200
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Yury Norov <yury.norov@gmail.com>
Cc:     Michael Mueller <mimu@linux.ibm.com>,
        Claudio Imbrenda <imbrenda@linux.ibm.com>,
        Christian Borntraeger <borntraeger@linux.ibm.com>,
        kvm@vger.kernel.org, linux-s390@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Janosch Frank <frankja@linux.ibm.com>,
        David Hildenbrand <david@redhat.com>,
        Heiko Carstens <hca@linux.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        Sven Schnelle <svens@linux.ibm.com>
Subject: Re: [PATCH v1 1/1] KVM: s390: Don't cast parameter in bit operations
Message-ID: <YiCWNdWd+AsLbDkp@smile.fi.intel.com>
References: <20220223164420.45344-1-andriy.shevchenko@linux.intel.com>
 <20220224123620.57fd6c8b@p-imbrenda>
 <3640a910-60fe-0935-4dfc-55bb65a75ce5@linux.ibm.com>
 <Yh+Qw6Pb+Cd9JDNa@smile.fi.intel.com>
 <Yh+m65BSfQgaDFwi@yury-laptop>
 <Yh+qDhd6FL9nlQdD@smile.fi.intel.com>
 <Yh+66v3OJZanfBLb@yury-laptop>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <Yh+66v3OJZanfBLb@yury-laptop>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
Precedence: bulk

On Wed, Mar 02, 2022 at 10:43:54AM -0800, Yury Norov wrote:
> On Wed, Mar 02, 2022 at 07:31:58PM +0200, Andy Shevchenko wrote:
> > On Wed, Mar 02, 2022 at 09:18:35AM -0800, Yury Norov wrote:
> > > On Wed, Mar 02, 2022 at 05:44:03PM +0200, Andy Shevchenko wrote:
> > > > On Thu, Feb 24, 2022 at 01:10:34PM +0100, Michael Mueller wrote:
> > > > > On 24.02.22 12:36, Claudio Imbrenda wrote:
> > > > 
> > > > ...
> > > > 
> > > > > we do that at several places
> > > > 
> > > > Thanks for pointing out.
> > > > 
> > > > > arch/s390/kernel/processor.c:	for_each_set_bit_inv(bit, (long
> > > > > *)&stfle_fac_list, MAX_FACILITY_BIT)
> > > > 
> > > > This one requires a separate change, not related to this patch.
> > > > 
> > > > > arch/s390/kvm/interrupt.c:	set_bit_inv(IPM_BIT_OFFSET + gisc, (unsigned long
> > > > > *) gisa);
> > > > 
> > > > This is done in the patch. Not sure how it appears in your list.
> > > > 
> > > > > arch/s390/kvm/kvm-s390.c:		set_bit_inv(vcpu->vcpu_id, (unsigned long *)
> > > > > sca->mcn);
> > > > > arch/s390/kvm/kvm-s390.c:		set_bit_inv(vcpu->vcpu_id, (unsigned long *)
> > > > > &sca->mcn);
> > > > 
> > > > These two should be fixed in a separate change.
> > > > 
> > > > Also this kind of stuff:
> > > > 
> > > > 	bitmap_copy(kvm->arch.cpu_feat, (unsigned long *) data.feat,
> > > > 	            KVM_S390_VM_CPU_FEAT_NR_BITS);
> > > > 
> > > > might require a new API like
> > > > 
> > > > bitmap_from_u64_array()
> > > > bitmap_to_u64_array()
> > > > 
> > > > Yury?
> > > 
> > > If BE32 is still the case then yes.
> > 
> > The whole point is to get rid of the bad pattern, while it may still work
> > in the particular case.
> 
> Then yes unconditionally. Is it already on table of s390 folks? If no,
> I can do it myself.
> 
> We have bitmap_from_arr32 and bitmap_to_arr32, so for 64-bit versions,
> we'd start from that.

Yep, thanks!

-- 
With Best Regards,
Andy Shevchenko