On Wed, Jan 22, 2014 at 6:25 AM, Wang Nan <wangnan0@huawei.com> wrote:

> ARM's kdump is actually corrupted (at least for omap4460), mainly because
> of
> cache problem: flush_icache_range can't reliably ensure the copied data
> correctly goes into RAM. After mmu turned off and jump to the trampoline,
> kexec
> always failed due to random undef instructions.
>
> This patch use ioremap to make sure the destnation of all memcpy() is
> uncachable memory, including copying of target kernel and trampoline.
>

AFAIK ioremap on RAM in forbidden in ARM and device memory that ioremap()
ends up creating is not meant for executable code.

Doesn't this trigger the WARN_ON() in _arm_ioremap_pfn_caller)?