linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: tip-bot for Boris Ostrovsky <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: mingo@kernel.org, linux-kernel@vger.kernel.org, hpa@zytor.com,
	tglx@linutronix.de, andy@strugglers.net,
	boris.ostrovsky@oracle.com
Subject: [tip:x86/urgent] x86/EISA: Don't probe EISA bus for Xen PV guests
Date: Tue, 11 Sep 2018 14:39:54 -0700	[thread overview]
Message-ID: <tip-6a92b11169a65b3f8cc512c75a252cbd0d096ba0@git.kernel.org> (raw)
In-Reply-To: <20180911195538.23289-1-boris.ostrovsky@oracle.com>

Commit-ID:  6a92b11169a65b3f8cc512c75a252cbd0d096ba0
Gitweb:     https://git.kernel.org/tip/6a92b11169a65b3f8cc512c75a252cbd0d096ba0
Author:     Boris Ostrovsky <boris.ostrovsky@oracle.com>
AuthorDate: Tue, 11 Sep 2018 15:55:38 -0400
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Tue, 11 Sep 2018 23:36:50 +0200

x86/EISA: Don't probe EISA bus for Xen PV guests

For unprivileged Xen PV guests this is normal memory and ioremap will
not be able to properly map it.

While at it, since ioremap may return NULL, add a test for pointer's
validity.

Reported-by: Andy Smith <andy@strugglers.net>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: hpa@zytor.com
Cc: xen-devel@lists.xenproject.org
Cc: jgross@suse.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180911195538.23289-1-boris.ostrovsky@oracle.com

---
 arch/x86/kernel/eisa.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/eisa.c b/arch/x86/kernel/eisa.c
index f260e452e4f8..e8c8c5d78dbd 100644
--- a/arch/x86/kernel/eisa.c
+++ b/arch/x86/kernel/eisa.c
@@ -7,11 +7,17 @@
 #include <linux/eisa.h>
 #include <linux/io.h>
 
+#include <xen/xen.h>
+
 static __init int eisa_bus_probe(void)
 {
-	void __iomem *p = ioremap(0x0FFFD9, 4);
+	void __iomem *p;
+
+	if (xen_pv_domain() && !xen_initial_domain())
+		return 0;
 
-	if (readl(p) == 'E' + ('I'<<8) + ('S'<<16) + ('A'<<24))
+	p = ioremap(0x0FFFD9, 4);
+	if (p && readl(p) == 'E' + ('I' << 8) + ('S' << 16) + ('A' << 24))
 		EISA_bus = 1;
 	iounmap(p);
 	return 0;

      parent reply	other threads:[~2018-09-11 21:40 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-11 19:55 [PATCH] x86/EISA: Don't probe EISA bus for Xen PV guests Boris Ostrovsky
2018-09-11 20:20 ` Thomas Gleixner
2018-09-11 20:30   ` Boris Ostrovsky
2018-09-11 21:39 ` tip-bot for Boris Ostrovsky [this message]

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=tip-6a92b11169a65b3f8cc512c75a252cbd0d096ba0@git.kernel.org \
    --to=tipbot@zytor.com \
    --cc=andy@strugglers.net \
    --cc=boris.ostrovsky@oracle.com \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-tip-commits@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=tglx@linutronix.de \
    /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).