linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>,
	Andy Lutomirski <luto@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, "H . Peter Anvin" <hpa@zytor.com>,
	Dan Williams <dan.j.williams@intel.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Jane Chu <jane.chu@oracle.com>,
	"Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>,
	Sean Christopherson <seanjc@google.com>,
	Tianyu Lan <Tianyu.Lan@microsoft.com>,
	Mike Rapoport <rppt@kernel.org>,
	Rick Edgecombe <rick.p.edgecombe@intel.com>,
	linux-mm@kvack.org, Borislav Petkov <bp@alien8.de>,
	x86@kernel.org
Subject: Re: [RFC 1/2] x86/mm/cpa: always fail when user address is passed
Date: Wed, 15 Jun 2022 06:11:03 -0700	[thread overview]
Message-ID: <YqnaZxcrqhWPVDUW@infradead.org> (raw)
In-Reply-To: <20220614063933.13030-2-42.hyeyoo@gmail.com>

On Tue, Jun 14, 2022 at 03:39:32PM +0900, Hyeonggon Yoo wrote:
> +
> +	if (WARN((IS_ENABLED(CONFIG_EFI) ? cpa->pgd != efi_mm.pgd : true)
> +		  && address <= TASK_SIZE_MAX,
> +		 KERN_WARNING "CPA: Got a user address"))
> +		return -EINVAL;

This looks rather unreadable.

Why not something like:

static bool cpa_addr_valid(struct cpa_data *cpa, unsigned long address)
{
	if (address > TASK_SIZE_MAX)
		return true;
	if (IS_ENABLED(CONFIG_EFI) && cpa->pgd == efi_mm.pgd)
		return true;
	return false;
}

....

	if (WARN_ON_ONCE(!cpa_addr_valid(cpa, address)))
		return -EINVAL;



  parent reply	other threads:[~2022-06-15 13:11 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-06-14  6:39 [RFC 0/2] CPA improvements Hyeonggon Yoo
2022-06-14  6:39 ` [RFC 1/2] x86/mm/cpa: always fail when user address is passed Hyeonggon Yoo
2022-06-14 17:52   ` Edgecombe, Rick P
2022-06-15  3:26     ` Hyeonggon Yoo
2022-06-15 18:17       ` Edgecombe, Rick P
2022-06-14 18:31   ` Dave Hansen
2022-06-16  8:49     ` Hyeonggon Yoo
2022-06-16 14:20       ` Dave Hansen
2022-06-20  8:08         ` Hyeonggon Yoo
2022-07-07 20:24           ` Dave Hansen
2022-06-15 13:11   ` Christoph Hellwig [this message]
2022-06-16  8:51     ` Hyeonggon Yoo
2022-06-14  6:39 ` [RFC 2/2] x86/mm/cpa: drop pgprot_clear_protnone_bits() Hyeonggon Yoo
2022-06-14  6:53   ` Hyeonggon Yoo
2022-06-14 18:23     ` Edgecombe, Rick P
2022-06-15  3:47       ` Hyeonggon Yoo
2022-06-15 18:18         ` Edgecombe, Rick P
2022-06-19 12:20           ` Hyeonggon Yoo

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=YqnaZxcrqhWPVDUW@infradead.org \
    --to=hch@infradead.org \
    --cc=42.hyeyoo@gmail.com \
    --cc=Tianyu.Lan@microsoft.com \
    --cc=aneesh.kumar@linux.ibm.com \
    --cc=bp@alien8.de \
    --cc=dan.j.williams@intel.com \
    --cc=dave.hansen@linux.intel.com \
    --cc=hpa@zytor.com \
    --cc=jane.chu@oracle.com \
    --cc=linux-mm@kvack.org \
    --cc=luto@kernel.org \
    --cc=mingo@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=peterz@infradead.org \
    --cc=rick.p.edgecombe@intel.com \
    --cc=rppt@kernel.org \
    --cc=seanjc@google.com \
    --cc=tglx@linutronix.de \
    --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;
as well as URLs for NNTP newsgroup(s).