Hi,
On 13/02/2017 11:00, Thomas Gleixner wrote:
> On Tue, 17 Jan 2017, Marc Zyngier wrote:
>> + typer = gic_read_typer(its_base + GITS_TYPER);
>> its->base = its_base;
>> its->phys_base = res->start;
>> - its->ite_size = ((gic_read_typer(its_base + GITS_TYPER) >> 4) & 0xf) +
>> 1;
>> + its->ite_size = ((typer >> 4) & 0xf) + 1;
>> + its->is_v4 = !!(typer & GITS_TYPER_VLPIS);
>> + if (its->is_v4 && !(typer & GITS_TYPER_VMOVP)) {
>> + int its_number;
>> +
>> + its_number = find_first_zero_bit(&its_list_map, 16);
>
> s/16/ITS_MAX_ENTITIES or whatever.
>
>> + if (its_number >= 16) {
>> + pr_err("ITS@%pa: No ITSList entry available!\n",
>> + &res->start);
>> + err = -EINVAL;
>> + goto out_free_its;
>> + }
>> +
>> + ctlr = readl_relaxed(its_base + GITS_CTLR);
>> + ctlr &= ~GITS_CTLR_ITS_NUMBER;
>> + ctlr |= its_number << GITS_CTLR_ITS_NUMBER_SHIFT;
>> + writel_relaxed(ctlr, its_base + GITS_CTLR);
>> + ctlr = readl_relaxed(its_base + GITS_CTLR);
>> + if ((ctlr & GITS_CTLR_ITS_NUMBER) != (its_number <<
>> GITS_CTLR_ITS_NUMBER_SHIFT)) {
>> + its_number = ctlr & GITS_CTLR_ITS_NUMBER;
>> + its_number >>= GITS_CTLR_ITS_NUMBER_SHIFT;
>> + }
>> +
>> + if (test_and_set_bit(its_number, &its_list_map)) {
>
> You just established above that the bit is not set. I assume that this is
> code which has no concurrency concerns....
I understand this covers the case where the ITS_number field is RO. In
such a case the its_number has changed just above compared to the first
find_first_zero_bit?
Besides
Reviewed-by: Eric Auger <eric.au...@redhat.com>
Thanks
Eric
>
> Thanks,
>
> tglx
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-ker...@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
