I am trying to debug a bcm43xx DMA problem on an x86_64 system with 3 GB RAM. Depending on the
particular chip and its implementation, dma transfers may use 64-, 32-, or 30-bit addressing, with
the problem interface using 30-bit addressing. From test prints, the correct mask (0x3FFFFFFF) is
supplied to pci_set_dma_mask and pci_set_consistent_dma_mask. Neither call returns an error. In
addition, several x86_64 systems with more than 1 GB RAM have worked with the current code.
If the system is booted with mem=1024M on the command line, it operates normally; however, it gets a
kernel NULL pointer dereference and panics when booted with either 2 or 3 GB RAM.
The config parameters in the processor section are as follows:
CONFIG_X86_64=y
CONFIG_64BIT=y
CONFIG_X86=y
CONFIG_ZONE_DMA32=y
CONFIG_LOCKDEP_SUPPORT=y
CONFIG_STACKTRACE_SUPPORT=y
CONFIG_SEMAPHORE_SLEEPERS=y
CONFIG_MMU=y
CONFIG_RWSEM_GENERIC_SPINLOCK=y
CONFIG_GENERIC_HWEIGHT=y
CONFIG_GENERIC_CALIBRATE_DELAY=y
CONFIG_X86_CMPXCHG=y
CONFIG_EARLY_PRINTK=y
CONFIG_GENERIC_ISA_DMA=y
CONFIG_GENERIC_IOMAP=y
CONFIG_ARCH_MAY_HAVE_PC_FDC=y
CONFIG_ARCH_POPULATES_NODE_MAP=y
CONFIG_DMI=y
CONFIG_AUDIT_ARCH=y
CONFIG_DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config"
I would appreciate any tips on debugging this problem. Are there any quantities that should be
dumped, etc?
Thanks,
Larry
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
