linux-mips
[Top] [All Lists]

MIPS and pci_alloc_consistent()?

To: linux-mips@oss.sgi.com
Subject: MIPS and pci_alloc_consistent()?
From: Shuanglin Wang <swang@mmc.atmel.com>
Date: Tue, 09 Oct 2001 16:23:49 -0500
Organization: ATMEL MMC
Reply-to: swang@mmc.atmel.com
Sender: owner-linux-mips@oss.sgi.com
I tried to use the pci_alloc_consistent() to allocate one-page  DMA'able memory for my device driver.  But, when booting up the system, it was always  failed to execute the pci_alloc_consistent() by showing some memory errors.

I traced the code to the function __alloc_page() in the file mm/page_alloc.c, and found the system called  "wakeup_kswapd()".  But at that time,  the kswapd process pointer is a NULL pointer and the wakeup-related codes don't check the pointer is NULL or not,  so the system was stopped because of dereferencing the null pointer.

I'm working on a MIPS SEAD-2 board using Linux kernel 2.4.3 MIPS distrinution.
Anybody has some ideas about the problem?  Or are there other convenient methods to allocate DMA'able memory?

Thanks,

-- 
Shuanglin Wang
Atmel Multimedia & Communications
3800 Gateway Centre, Suite 311
Morrisville, NC 27560
 
<Prev in Thread] Current Thread [Next in Thread>