On Wed, Apr 03, 2013 at 05:38:25PM -0700, Yinghai Lu wrote: > Vivek found old kexec-tools does not work new kernel anymore. > > So change back crashkernel= back to old behavoir, and add crashkernel_high= > to let user decide if buffer could be above 4G, and also new kexec-tools will > be needed. > > v2: let crashkernel=X override crashkernel_high= > update description about _high will be ignored by crashkernel=X > > Signed-off-by: Yinghai Lu <ying...@kernel.org> > > --- > Documentation/kernel-parameters.txt | 11 +++++++++-- > arch/x86/kernel/setup.c | 24 +++++++++++++++++++----- > include/linux/kexec.h | 2 ++ > kernel/kexec.c | 9 +++++++++ > 4 files changed, 39 insertions(+), 7 deletions(-) > > Index: linux-2.6/Documentation/kernel-parameters.txt > =================================================================== > --- linux-2.6.orig/Documentation/kernel-parameters.txt > +++ linux-2.6/Documentation/kernel-parameters.txt > @@ -603,9 +603,14 @@ bytes respectively. Such letter suffixes > a memory unit (amount[KMG]). See also > Documentation/kdump/kdump.txt for an example. > > + crashkernel_high=size[KMG] > + [KNL, x86_64] range could be above 4G. Allow kernel > + to allocate physical memory region from top, so could > + be above 4G if system have more than 4G ram installed.
Also specify "otherwise memory will be allocated below 4G, if available". > + It will be ignored if crashkernel=X is specified. > crashkernel_low=size[KMG] > - [KNL, x86_64] range under 4G. When crashkernel= is > - passed, kernel allocate physical memory region > + [KNL, x86_64] range under 4G. When crashkernel_high= is > + passed, kernel could allocate physical memory region > above 4G, that cause second kernel crash on system > that need swiotlb later. Kernel would try to allocate > some region below 4G automatically. This one let > @@ -614,6 +619,8 @@ bytes respectively. Such letter suffixes > 0: to disable low allocation on systems that do not > need swiotlb, that will save 72M low ram in first > kernel. > + It will be ignored when crashkernel_high=X is not used > + or return from that is below 4G. Replace "return from that" with "memory reserved". Vivek -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
