From: David Laight <David.Laight@ACULAB.COM>
To: 'Dave Hansen' <dave.hansen@intel.com>,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
"tglx@linutronix.de" <tglx@linutronix.de>,
"mingo@redhat.com" <mingo@redhat.com>,
"bp@alien8.de" <bp@alien8.de>,
"luto@kernel.org" <luto@kernel.org>,
"peterz@infradead.org" <peterz@infradead.org>
Cc: "ak@linux.intel.com" <ak@linux.intel.com>,
"dan.j.williams@intel.com" <dan.j.williams@intel.com>,
"david@redhat.com" <david@redhat.com>,
"hpa@zytor.com" <hpa@zytor.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"sathyanarayanan.kuppuswamy@linux.intel.com"
<sathyanarayanan.kuppuswamy@linux.intel.com>,
"seanjc@google.com" <seanjc@google.com>,
"thomas.lendacky@amd.com" <thomas.lendacky@amd.com>,
"x86@kernel.org" <x86@kernel.org>
Subject: RE: [PATCHv4 3/3] x86/tdx: Handle load_unaligned_zeropad() page-cross to a shared page
Date: Thu, 16 Jun 2022 06:35:44 +0000 [thread overview]
Message-ID: <9708d6cf72184b7788bfb95ea1f46faf@AcuMS.aculab.com> (raw)
In-Reply-To: <db63853f-dbd8-7593-032d-e674046bff8e@intel.com>
From: Dave Hansen
> Sent: 16 June 2022 00:35
>
> On 6/15/22 15:52, Kirill A. Shutemov wrote:
> >> + vaddr = (unsigned long)insn_get_addr_ref(&insn, regs);
> >> + if (vaddr / PAGE_SIZE != (vaddr + size) / PAGE_SIZE)
> > Oops. I just realized it has off-by-one. It supposed to be:
> >
> > if (vaddr / PAGE_SIZE != (vaddr + size - 1) / PAGE_SIZE)
>
> That was bugging me. Glad you caught this.
>
> Wouldn't this be more obviously correct?
>
> if (ALIGN_DOWN(vaddr, PAGE_SIZE) !=
> ALIGN_DOWN(vaddr + size, PAGE_SIZE))
> ...
>
> I don't think we have a PAGE_ALIGN_DOWN().
Or:
if ((vaddr ^ (vaddr + size - 1)) >> PAGE_SHIFT)
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
next prev parent reply other threads:[~2022-06-16 6:35 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-14 12:01 [PATCHv4 0/3] An updated version of the load_unaligned_zeropad() fix Kirill A. Shutemov
2022-06-14 12:01 ` [PATCHv4 1/3] x86/tdx: Fix early #VE handling Kirill A. Shutemov
2022-06-17 21:53 ` [tip: x86/urgent] " tip-bot2 for Kirill A. Shutemov
2022-06-14 12:01 ` [PATCHv4 2/3] x86/tdx: Clarify RIP adjustments in #VE handler Kirill A. Shutemov
2022-06-17 21:53 ` [tip: x86/urgent] " tip-bot2 for Kirill A. Shutemov
2022-06-14 12:01 ` [PATCHv4 3/3] x86/tdx: Handle load_unaligned_zeropad() page-cross to a shared page Kirill A. Shutemov
2022-06-15 15:27 ` Dave Hansen
2022-06-15 17:10 ` Kirill A. Shutemov
2022-06-15 21:55 ` Dave Hansen
2022-06-15 22:43 ` Kirill A. Shutemov
2022-06-15 22:49 ` Dave Hansen
2022-06-15 23:16 ` Kirill A. Shutemov
2022-06-15 18:12 ` Dave Hansen
2022-06-15 22:32 ` Kirill A. Shutemov
2022-06-15 22:36 ` Dave Hansen
2022-06-15 23:16 ` Kirill A. Shutemov
2022-06-15 22:52 ` Kirill A. Shutemov
2022-06-15 23:34 ` Dave Hansen
2022-06-16 1:19 ` Kirill A. Shutemov
2022-06-16 6:35 ` David Laight [this message]
2022-06-17 21:53 ` [tip: x86/urgent] " tip-bot2 for Kirill A. Shutemov
2022-06-17 22:41 ` tip-bot2 for Kirill A. Shutemov
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=9708d6cf72184b7788bfb95ea1f46faf@AcuMS.aculab.com \
--to=david.laight@aculab.com \
--cc=ak@linux.intel.com \
--cc=bp@alien8.de \
--cc=dan.j.williams@intel.com \
--cc=dave.hansen@intel.com \
--cc=david@redhat.com \
--cc=hpa@zytor.com \
--cc=kirill.shutemov@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=sathyanarayanan.kuppuswamy@linux.intel.com \
--cc=seanjc@google.com \
--cc=tglx@linutronix.de \
--cc=thomas.lendacky@amd.com \
--cc=x86@kernel.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox