mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: "Christian König" <ckoenig.leichtzumerken@gmail.com>
To: helgaas@kernel.org
Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] x86/PCI: limit the size of the 64bit BAR to 256GB
Date: Mon, 11 Dec 2017 16:04:52 +0100	[thread overview]
Message-ID: <20171211150452.23518-1-christian.koenig@amd.com> (raw)

Xen hides a bit of system memory from the OS for its own purpose by
intercepting e820. This memory is unfortunately not reported as
reserved, but rather completely invisible.

Avoid this address space collision and possible similar problems by
limiting the size of the newly allocated root hub window to 256GB which
should be sufficient for the short term.

Signed-off-by: Christian König <christian.koenig@amd.com>
---
 arch/x86/pci/fixup.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c
index 8f86060f5cf6..ed8bc6ab0573 100644
--- a/arch/x86/pci/fixup.c
+++ b/arch/x86/pci/fixup.c
@@ -702,7 +702,7 @@ static void pci_amd_enable_64bit_bar(struct pci_dev *dev)
 	res->name = "PCI Bus 0000:00";
 	res->flags = IORESOURCE_PREFETCH | IORESOURCE_MEM |
 		IORESOURCE_MEM_64 | IORESOURCE_WINDOW;
-	res->start = 0x100000000ull;
+	res->start = 0xbd00000000ull;
 	res->end = 0xfd00000000ull - 1;
 
 	/* Just grab the free area behind system memory for this */
-- 
2.11.0

             reply	other threads:[~2017-12-11 15:05 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-12-11 15:04 Christian König [this message]
2017-12-12 18:12 ` Bjorn Helgaas
2017-12-12 18:38   ` Christian König
2017-12-12 18:49     ` Boris Ostrovsky

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=20171211150452.23518-1-christian.koenig@amd.com \
    --to=ckoenig.leichtzumerken@gmail.com \
    --cc=helgaas@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.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

all inboxes | Powered by JetHome®