From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Mike Fox" Date: Tue, 08 Apr 2003 21:59:56 +0000 Subject: [Linux-ia64] mmap crashes system after mapping PCI device into user space and reading and writing. MIME-Version: 1 Content-Type: multipart/mixed; boundary="----=_NextPart_000_0020_01C2FDF8.AA4069A0" Message-Id: List-Id: To: linux-ia64@vger.kernel.org This is a multi-part message in MIME format. ------=_NextPart_000_0020_01C2FDF8.AA4069A0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Hi, =20 I am running kernel version 2.4.19 and I am getting a system crash when = I mmap my PCI device into user space and access it. =20 It seems to be the same issue that was posted earlier in the following = post, which had no response: =20 Has anyone tried using mmap to remap PCI device memory into user space? = I have seen the following problem: If I do the mmap, it returns = successfully, and I can indeed access the device memory. Unfortunately, the system = will hang within about a minute after doing so. I do not get an oops, or = crash of any kind, simply no further response form the machine. If I just do = the mmap and then munmap the system will not hang. But if I do one access = to the mmapped address, the system will hang. I am using the = remap_page_range call in my mmap routine, and this same code works on x86 and Alpha platforms. I found it odd that it takes a while for the system to hang after the access, is their something special I have to do for this to = work on IA64? I am running 2.4.1 with the 1/31 patch, although this problem occurs on all previous kernels I have tried. Thanks in advance for any insight anyone might have. =20 Thanks for any help you can give. I'm new to Linux and IA64 and I am in = a rush to port a PCI driver and API. =20 Thanks, Mike Fox. =20 =20 ------=_NextPart_000_0020_01C2FDF8.AA4069A0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Hi,

 

I am running kernel version 2.4.19 and I am getting a = system crash when I mmap my PCI device into user space and access = it.

 

It seems to be the same issue that was posted earlier = in the following post, which had no response:

 

Has anyone tried using mmap to remap PCI =
device memory into user space?  I
have seen =
the following problem:  If I do the mmap, it returns =
successfully,
and I can =
indeed access the device memory.  Unfortunately, the system =
will
hang =
within about a minute after doing so.  I do not get an oops, or =
crash
of any =
kind, simply no further response form the machine.  If I just do =
the
mmap and =
then munmap the system will not hang.  But if I do one access =
to
the =
mmapped address, the system will hang.  I am using the =
remap_page_range
call in =
my mmap routine, and this same code works on x86 and =
Alpha
platforms.  I found it odd that it takes =
a while for the system to hang
after the =
access, is their something special I have to do for this to =
work
on =
IA64?  I am running 2.4.1 with the 1/31 patch, although this =
problem
occurs on =
all previous kernels I have tried.  Thanks in advance for =
any
insight =
anyone might have.

 

Thanks for any help you can give. I’m new to = Linux and IA64 and I am in a rush to port a PCI driver and API.

 

Thanks,

Mike Fox.

 

 

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