From: "Li, Xin3" <xin3.li@intel.com>
To: "Hansen, Dave" <dave.hansen@intel.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"x86@kernel.org" <x86@kernel.org>
Cc: "tglx@linutronix.de" <tglx@linutronix.de>,
"mingo@redhat.com" <mingo@redhat.com>,
"bp@alien8.de" <bp@alien8.de>,
"dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>,
"hpa@zytor.com" <hpa@zytor.com>,
"bigeasy@linutronix.de" <bigeasy@linutronix.de>,
"Liu, Yujie" <yujie.liu@intel.com>,
"Kang, Shan" <shan.kang@intel.com>
Subject: RE: [PATCH 1/1] x86/vdso: use the right GDT_ENTRY_CPUNODE for 32-bit getcpu() on 64-bit kernel
Date: Mon, 13 Mar 2023 17:42:46 +0000 [thread overview]
Message-ID: <SA1PR11MB6734CF1607F263CB8389F5F2A8B99@SA1PR11MB6734.namprd11.prod.outlook.com> (raw)
In-Reply-To: <5e84fd48-459d-8850-d26f-860c6d34a9ad@intel.com>
> > +#ifndef BUILD_VDSO32_64
> > #define GDT_ENTRY_CPUNODE 28
> > +#else
> > +#define GDT_ENTRY_CPUNODE 15
> > +#endif
>
> Isn't this kinda a hack?
>
> First, it means that we'll now have two duplicate versions of this:
>
> #define GDT_ENTRY_CPUNODE 15
>
> in the same file.
>
> Second, if any other users of fake_32bit_build.h for the VDSO show up, they'll
> need a similar #ifdef.
>
> I think I'd much rather if we define all of the GDT_ENTRY_* macros in
> *one* place, then make that *one* place depend on BUILD_VDSO32_64.
Sounds a better way, let me try.
> Also, about the *silent* failure... Do we not have a selftest for this somewhere?
When lsl is used, we should check ZF which indicates whether the segment limit
is loaded successfully. Seems we need to refactor vdso_read_cpunode() a bit.
Xin
next prev parent reply other threads:[~2023-03-13 17:42 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-11 8:48 [PATCH 1/1] x86/vdso: use the right GDT_ENTRY_CPUNODE for 32-bit getcpu() on 64-bit kernel Xin Li
2023-03-13 15:22 ` Dave Hansen
2023-03-13 17:42 ` Li, Xin3 [this message]
2023-03-18 8:14 ` Li, Xin3
2023-03-29 8:50 ` Li, Xin3
2023-03-29 23:11 ` Li, Xin3
2023-03-29 23:59 ` H. Peter Anvin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=SA1PR11MB6734CF1607F263CB8389F5F2A8B99@SA1PR11MB6734.namprd11.prod.outlook.com \
--to=xin3.li@intel.com \
--cc=bigeasy@linutronix.de \
--cc=bp@alien8.de \
--cc=dave.hansen@intel.com \
--cc=dave.hansen@linux.intel.com \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=shan.kang@intel.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
--cc=yujie.liu@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.