# WARNING:  You are probably using the kernel's swiotlb interf

## anderlin

At every boot I get this message:

```
NVRM: loading NVIDIA Linux x86_64 NVIDIA Kernel Module  1.0-6111  Tue Jul 27 07:58:17 PDT 2004

NVRM: WARNING:  You are probably using the kernel's swiotlb interface.

NVRM: Be very careful with this interface, as it is easy

NVRM: to exhaust this interface's memory buffer, at which

NVRM: point it panics the kernel.  Please increase the size

NVRM: of this buffer by specifying a larger buffer size with

NVRM: the swiotlb kernel option, eg: "swiotlb=16384"

```

What does this mean? I couldn't find any info on swiotlb...

```
uname -a

Linux anderlin64 2.6.9-gentoo-r6 #12 Sat Dec 4 02:08:46 CET 2004 x86_64 AMD Athlon(tm) 64 Processor 3200+ AuthenticAMD GNU/Linux

```

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## transienteagle

Anderlin,

google for software TLB (translation look−aside buffer) which will give you the answers to what you need.

You need to add swiotlb=16384 to your kernel boot line 

ie in grub;

title Gentoo Linux 2.6.9

        root (hd0,0)

        kernel /gentoo2 root=/dev/hdd3 swiotlb=16384

        color magenta/blue black/magenta

savedefault

boot

rgds

TE

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## anderlin

Thank you for the keywords. I now understand it is some sort of software cache. However, I changed the boot option, but still get this:

```
# cat /proc/cmdline

root=/dev/md0 swiotlb=16384 console=tty0

# dmesg | grep NVRM

NVRM: loading NVIDIA Linux x86_64 NVIDIA Kernel Module  1.0-6111  Tue Jul 27 07:58:17 PDT 2004

NVRM: WARNING:  You are probably using the kernel's swiotlb interface.

NVRM: Be very careful with this interface, as it is easy

NVRM: to exhaust this interface's memory buffer, at which

NVRM: point it panics the kernel.  Please increase the size

NVRM: of this buffer by specifying a larger buffer size with

NVRM: the swiotlb kernel option, eg: "swiotlb=16384"

anderlin64 anderlin #

```

How come it still complains?

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