linux-kernel - Re: [PATCH 3/5] irqchip: gicv3-its: use 64KB page as default granule

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <54CC3105.1050200@huawei.com>
Date:	Sat, 31 Jan 2015 09:33:57 +0800
From:	"Yun Wu (Abel)" <wuyun.wu@...wei.com>
To:	Marc Zyngier <marc.zyngier@....com>
CC:	"tglx@...utronix.de" <tglx@...utronix.de>,
	"jason@...edaemon.net" <jason@...edaemon.net>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH 3/5] irqchip: gicv3-its: use 64KB page as default granule

On 2015/1/31 3:18, Marc Zyngier wrote:

> On 30/01/15 07:46, Yun Wu wrote:
>> The field of page size in register GITS_BASERn might be read-only
>> if an implementation only supports a single, fixed page size. But
>> currently the ITS driver will throw out an error when PAGE_SIZE
>> is less than the minimum size supported by an ITS. So addressing
>> this problem by using 64KB pages as default granule for all the
>> ITS base tables.
> 
> Do you actually know of an implementation with such a behaviour?

Yes, Hisilicon implemented a fixed page size of 16KB.

> 
>> Signed-off-by: Yun Wu <wuyun.wu@...wei.com>
>> ---
>>  drivers/irqchip/irq-gic-v3-its.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
>> index 2a08d85..430bc92 100644
>> --- a/drivers/irqchip/irq-gic-v3-its.c
>> +++ b/drivers/irqchip/irq-gic-v3-its.c
>> @@ -801,7 +801,7 @@ static int its_alloc_tables(struct its_node *its)
>>  	int err;
>>  	int i;
>>  	int size;
>> -	int psz = PAGE_SIZE;
>> +	int psz = SZ_64K;
>>  	u64 shr = GITS_BASER_InnerShareable;
>>
>>  	for (i = 0; i < GITS_BASER_NR_REGS; i++) {
> 
> Assuming such an implementation exists, you'll have to rebase this on
> top of the patch I mentioned in my reply to patch #1.
> 

OK, I will.

Thanks,
	Abel

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/