Hi all, PING!
Is there any further comment or suggetion about this patchset? Thanks Baoquan On 05/20/17 at 08:02pm, Baoquan He wrote: > This is v2 post. > > This patchset is trying to fix a bug that SGI UV system casually hang > during boot with KASLR enabled. The root cause is that mm KASLR adapts > size of the direct mapping section only based on the system RAM size. > Then later when map SGI UV MMIOH region into the direct mapping during > rest_init() invocation, it might go beyond of the directing mapping > section and step into VMALLOC or VMEMMAP area, then BUG_ON triggered. > > The fix is adding a helper function is_early_uv_system to check UV system > earlier, then call the helper function in kernel_randomize_memory() to > check if it's a SGI UV system, if yes, we keep the size of direct mapping > section to be 64TB just as nokslr. > > With this fix, SGI UV system can have 64TB direct mapping size always, > and the starting address of direct mapping/vmalloc/vmemmap and the padding > between them can still be randomized to enhance the system security. > > v1->v2: > 1. Mike suggested making is_early_uv_system() an inline function and be > put in include/asm/uv/uv.h so that they can adjust them easier in the > future. > > 2. Split the v1 code into uv part and mm KASLR part as Mike suggested. > > Baoquan He (2): > x86/UV: Introduce a helper function to check UV system at earlier > stage > x86/mm/KASLR: Do not adapt the size of the direct mapping section for > SGI UV system > > arch/x86/include/asm/uv/uv.h | 6 ++++++ > arch/x86/mm/kaslr.c | 3 ++- > 2 files changed, 8 insertions(+), 1 deletion(-) > > -- > 2.5.5 >
