diff options
| author | Anton Blanchard <anton@samba.org> | 2010-08-24 14:23:44 +0000 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2010-11-29 15:48:17 +1100 |
| commit | d72e063bb32c06c6c1cec14f6857b7c37ba62d7a (patch) | |
| tree | 9bab39d568bee4b95e37700b0e87ef7346525953 | |
| parent | 64ff31287693c1f325cb9cb049569c1611438ef1 (diff) | |
powerpc/kdump: Override crash_free_reserved_phys_range to avoid freeing RTAS
The crashkernel region will almost always overlap RTAS. If we free the
crashkernel region via "echo 0 > /sys/kernel/kexec_crash_size" then we will
free RTAS and the machine will crash in confusing and exciting ways.
Override crash_free_reserved_phys_range and check for overlap with RTAS.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| -rw-r--r-- | arch/powerpc/kernel/crash_dump.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/crash_dump.c b/arch/powerpc/kernel/crash_dump.c index 8e05c16344e4..0a2af50243cb 100644 --- a/arch/powerpc/kernel/crash_dump.c +++ b/arch/powerpc/kernel/crash_dump.c @@ -19,6 +19,7 @@ #include <asm/prom.h> #include <asm/firmware.h> #include <asm/uaccess.h> +#include <asm/rtas.h> #ifdef DEBUG #include <asm/udbg.h> @@ -141,3 +142,35 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, return csize; } + +#ifdef CONFIG_PPC_RTAS +/* + * The crashkernel region will almost always overlap the RTAS region, so + * we have to be careful when shrinking the crashkernel region. + */ +void crash_free_reserved_phys_range(unsigned long begin, unsigned long end) +{ + unsigned long addr; + const u32 *basep, *sizep; + unsigned int rtas_start = 0, rtas_end = 0; + + basep = of_get_property(rtas.dev, "linux,rtas-base", NULL); + sizep = of_get_property(rtas.dev, "rtas-size", NULL); + + if (basep && sizep) { + rtas_start = *basep; + rtas_end = *basep + *sizep; + } + + for (addr = begin; addr < end; addr += PAGE_SIZE) { + /* Does this page overlap with the RTAS region? */ + if (addr <= rtas_end && ((addr + PAGE_SIZE) > rtas_start)) + continue; + + ClearPageReserved(pfn_to_page(addr >> PAGE_SHIFT)); + init_page_count(pfn_to_page(addr >> PAGE_SHIFT)); + free_page((unsigned long)__va(addr)); + totalram_pages++; + } +} +#endif |