32e62c636a
This closes a couple holes in our attribute aliasing avoidance scheme:
- The current kernel fails mmaps of some /dev/mem MMIO regions because
they don't appear in the EFI memory map. This keeps X from working
on the Intel Tiger box.
- The current kernel allows UC mmap of the 0-1MB region of
/sys/.../legacy_mem even when the chipset doesn't support UC
access. This causes an MCA when starting X on HP rx7620 and rx8620
boxes in the default configuration.
There's more detail in the Documentation/ia64/aliasing.txt file this
adds, but the general idea is that if a region might be covered by
a granule-sized kernel identity mapping, any access via /dev/mem or
mmap must use the same attribute as the identity mapping.
Otherwise, we fall back to using an attribute that is supported
according to the EFI memory map, or to using UC if the EFI memory
map doesn't mention the region.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
|
||
|---|---|---|
| .. | ||
| IRQ-redir.txt | ||
| README | ||
| aliasing.txt | ||
| efirtc.txt | ||
| fsys.txt | ||
| mca.txt | ||
| serial.txt | ||
README
Linux kernel release 2.4.xx for the IA-64 Platform
These are the release notes for Linux version 2.4 for IA-64
platform. This document provides information specific to IA-64
ONLY, to get additional information about the Linux kernel also
read the original Linux README provided with the kernel.
INSTALLING the kernel:
- IA-64 kernel installation is the same as the other platforms, see
original README for details.
SOFTWARE REQUIREMENTS
Compiling and running this kernel requires an IA-64 compliant GCC
compiler. And various software packages also compiled with an
IA-64 compliant GCC compiler.
CONFIGURING the kernel:
Configuration is the same, see original README for details.
COMPILING the kernel:
- Compiling this kernel doesn't differ from other platform so read
the original README for details BUT make sure you have an IA-64
compliant GCC compiler.
IA-64 SPECIFICS
- General issues:
o Hardly any performance tuning has been done. Obvious targets
include the library routines (IP checksum, etc.). Less
obvious targets include making sure we don't flush the TLB
needlessly, etc.
o SMP locks cleanup/optimization
o IA32 support. Currently experimental. It mostly works.