linux-kernel - Re: [PATCH v9 14/21] ACPI / processor: Make it possible to get CPU hardware ID via GICC

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: <CAJZ5v0iHstGiXLT0DPHu2=xH3bD-kD=WCqfuB1XaTgNSnthcLQ@mail.gmail.com>
Date:	Thu, 5 Mar 2015 14:13:58 +0100
From:	"Rafael J. Wysocki" <rafael@...nel.org>
To:	Catalin Marinas <catalin.marinas@....com>
Cc:	Hanjun Guo <guohanjun@...wei.com>,
	"Rafael J. Wysocki" <rjw@...ysocki.net>,
	Hanjun Guo <hanjun.guo@...aro.org>,
	Mark Rutland <mark.rutland@....com>,
	Ashwin Chaugule <ashwinc@...eaurora.org>,
	Lorenzo Pieralisi <Lorenzo.Pieralisi@....com>,
	Robert Richter <rric@...nel.org>,
	Graeme Gregory <graeme.gregory@...aro.org>,
	Arnd Bergmann <arnd@...db.de>,
	ACPI Devel Maling List <linux-acpi@...r.kernel.org>,
	Marc Zyngier <marc.zyngier@....com>,
	Timur Tabi <timur@...eaurora.org>,
	"linaro-acpi@...ts.linaro.org" <linaro-acpi@...ts.linaro.org>,
	Will Deacon <will.deacon@....com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Grant Likely <grant.likely@...aro.org>,
	Mark Brown <broonie@...nel.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	suravee.suthikulpanit@....com, Sudeep Holla <Sudeep.Holla@....com>,
	Olof Johansson <olof@...om.net>, Jon Masters <jcm@...hat.com>
Subject: Re: [PATCH v9 14/21] ACPI / processor: Make it possible to get CPU
 hardware ID via GICC

On Thu, Mar 5, 2015 at 12:27 PM, Catalin Marinas
<catalin.marinas@....com> wrote:
> On Thu, Mar 05, 2015 at 04:03:21PM +0800, Hanjun Guo wrote:
>> On 2015/3/5 6:46, Rafael J. Wysocki wrote:
>> > IMO, you really need to define phys_cpuid_t in a common place or people will
>> > forget that it may be 64-bit, because they'll only be looking at their arch.
>>
>> Since x86 and ARM64 are using different types for phys_cpuid_t, we need to
>> introduce something like following if define it in common place:
>>
>> in linux/acpi.h,
>>
>> #if defined(CONFIG_X86) || defined(CONFIG_IA64)
>> typedef u32 phys_cpuid_t;
>> #define PHYS_CPUID_INVALID (phys_cpuid_t)(-1)
>> #else if defined(CONFIG_ARM64)
>> typedef u64 phys_cpuid_t;
>> #define PHYS_CPUID_INVALID INVALID_HWID
>> #endif
>>
>> I think it's awful, did I miss something?

Well, you can define the type and PHYS_CPUID_INVALID in the arch
code and then do this in a common header:

#ifndef PHYS_CPUID_INVALID
typedef u32 phys_cpuid_t;
#define PHYS_CPUID_INVALID (phys_cpuid_t)(-1)
#endif

That would allow you to avoid the need to duplicate the
definitions where it is not necessary.

> I also think that's awful. I'm rather in favour of a per-arch
> phys_cpuid_t.

OK, so what about the above?

Rafael
--
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/