Fork of alistair23 Linux kernel for reMarkable from https://github.com/alistair23/linux
172dcd935c
Currently we allocate the exception vector on systems which use a
vectored interrupt mode, but otherwise attempt to reuse whatever
exception vector the bootloader uses.
This can be problematic for a number of reasons:
1) The memory isn't properly marked reserved in the memblock
allocator. We've relied on the fact that EBase is generally in the
memory below the kernel image which we don't free, but this is
about to change.
2) Recent versions of U-Boot place their exception vector high in
kseg0, in memory which isn't protected by being lower than the
kernel anyway & can end up being clobbered.
3) We are unnecessarily reliant upon there being memory at the address
EBase points to upon entry to the kernel. This is often the case,
but if the bootloader doesn't configure EBase & leaves it with its
default value then we rely upon there being memory at physical
address 0 for no good reason.
Improve this situation by allocating the exception vector in all cases
when running on MIPSr2 or higher, and reserving the memory for MIPSr1 or
lower. This ensures we don't clobber the exception vector in any
configuration, and for MIPSr2 & higher removes the need for memory at
physical address 0.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Tested-by: Serge Semin <fancer.lancer@gmail.com>
Cc: linux-mips@vger.kernel.org
|
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.