BMC/Intel-BMC/linux.git/arch/sparc/mm/init_64.c, branch dev

mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute

2015-06-25T00:49:44+00:00

Some high end Intel Xeon systems report uncorrectable memory errors as a recoverable machine check. Linux has included code for some time to process these and just signal the affected processes (or even recover completely if the error was in a read only page that can be replaced by reading from disk). But we have no recovery path for errors encountered during kernel code execution. Except for some very specific cases were are unlikely to ever be able to recover. Enter memory mirroring. Actually 3rd generation of memory mirroing. Gen1: All memory is mirrored Pro: No s/w enabling - h/w just gets good data from other side of the mirror Con: Halves effective memory capacity available to OS/applications Gen2: Partial memory mirror - just mirror memory begind some memory controllers Pro: Keep more of the capacity Con: Nightmare to enable. Have to choose between allocating from mirrored memory for safety vs. NUMA local memory for performance Gen3: Address range partial memory mirror - some mirror on each memory controller Pro: Can tune the amount of mirror and keep NUMA performance Con: I have to write memory management code to implement The current plan is just to use mirrored memory for kernel allocations. This has been broken into two phases: 1) This patch series - find the mirrored memory, use it for boot time allocations 2) Wade into mm/page_alloc.c and define a ZONE_MIRROR to pick up the unused mirrored memory from mm/memblock.c and only give it out to select kernel allocations (this is still being scoped because page_alloc.c is scary). This patch (of 3): Add extra "flags" to memblock to allow selection of memory based on attribute. No functional changes Signed-off-by: Tony Luck Cc: Xishi Qiu Cc: Hanjun Guo Cc: Xiexiuqi Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Yinghai Lu Cc: Naoya Horiguchi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'linus' into sched/core, to resolve conflict

2015-06-02T06:05:42+00:00

Conflicts: arch/sparc/include/asm/topology_64.h Signed-off-by: Ingo Molnar

sparc: Resolve conflict between sparc v9 and M7 on usage of bit 9 of TTE

2015-06-01T05:15:01+00:00

sparc: Resolve conflict between sparc v9 and M7 on usage of bit 9 of TTE Bit 9 of TTE is CV (Cacheable in V-cache) on sparc v9 processor while the same bit 9 is MCDE (Memory Corruption Detection Enable) on M7 processor. This creates a conflicting usage of the same bit. Kernel sets TTE.cv bit on all pages for sun4v architecture which works well for sparc v9 but enables memory corruption detection on M7 processor which is not the intent. This patch adds code to determine if kernel is running on M7 processor and takes steps to not enable memory corruption detection in TTE erroneously. Signed-off-by: Khalid Aziz Signed-off-by: David S. Miller

mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler

2015-05-19T06:39:15+00:00

Introduce faulthandler_disabled() and use it to check for irq context and disabled pagefaults (via pagefault_disable()) in the pagefault handlers. Please note that we keep the in_atomic() checks in place - to detect whether in irq context (in which case preemption is always properly disabled). In contrast, preempt_disable() should never be used to disable pagefaults. With !CONFIG_PREEMPT_COUNT, preempt_disable() doesn't modify the preempt counter, and therefore the result of in_atomic() differs. We validate that condition by using might_fault() checks when calling might_sleep(). Therefore, add a comment to faulthandler_disabled(), describing why this is needed. faulthandler_disabled() and pagefault_disable() are defined in linux/uaccess.h, so let's properly add that include to all relevant files. This patch is based on a patch from Thomas Gleixner. Reviewed-and-tested-by: Thomas Gleixner Signed-off-by: David Hildenbrand Signed-off-by: Peter Zijlstra (Intel) Cc: David.Laight@ACULAB.COM Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: airlied@linux.ie Cc: akpm@linux-foundation.org Cc: benh@kernel.crashing.org Cc: bigeasy@linutronix.de Cc: borntraeger@de.ibm.com Cc: daniel.vetter@intel.com Cc: heiko.carstens@de.ibm.com Cc: herbert@gondor.apana.org.au Cc: hocko@suse.cz Cc: hughd@google.com Cc: mst@redhat.com Cc: paulus@samba.org Cc: ralf@linux-mips.org Cc: schwidefsky@de.ibm.com Cc: yang.shi@windriver.com Link: http://lkml.kernel.org/r/1431359540-32227-7-git-send-email-dahi@linux.vnet.ibm.com Signed-off-by: Ingo Molnar

sparc: Fix /proc/kcore

2015-03-19T02:15:28+00:00

/proc/kcore investigates the "System RAM" elements in /proc/iomem to initialize it's memory tables. Therefore we have to register them before it tries to do so. kcore uses device_initcall() so let's use arch_initcall() for the registry. Also we need ARCH_PROC_KCORE_TEXT to get the virtual addresses of the kernel image correct. Reported-by: David Ahern Signed-off-by: David S. Miller

mm/debug-pagealloc: make debug-pagealloc boottime configurable

2014-12-13T20:42:48+00:00

Now, we have prepared to avoid using debug-pagealloc in boottime. So introduce new kernel-parameter to disable debug-pagealloc in boottime, and makes related functions to be disabled in this case. Only non-intuitive part is change of guard page functions. Because guard page is effective only if debug-pagealloc is enabled, turning off according to debug-pagealloc is reasonable thing to do. Signed-off-by: Joonsoo Kim Cc: Mel Gorman Cc: Johannes Weiner Cc: Minchan Kim Cc: Dave Hansen Cc: Michal Nazarewicz Cc: Jungsoo Son Cc: Ingo Molnar Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sparc64: Kill unnecessary tables and increase MAX_BANKS.

2014-10-05T23:53:40+00:00

swapper_low_pmd_dir and swapper_pud_dir are actually completely useless and unnecessary. We just need swapper_pg_dir[]. Naturally the other page table chunks will be allocated on an as-needed basis. Since the kernel actually accesses these tables in the PAGE_OFFSET view, there is not even a TLB locality advantage of placing them in the kernel image. Use the hard coded vmlinux.ld.S slot for swapper_pg_dir which is naturally page aligned. Increase MAX_BANKS to 1024 in order to handle heavily fragmented virtual guests. Even with this MAX_BANKS increase, the kernel is 20K+ smaller. Signed-off-by: David S. Miller Acked-by: Bob Picco

sparc64: Adjust vmalloc region size based upon available virtual address bits.

2014-10-05T23:53:40+00:00

In order to accomodate embedded per-cpu allocation with large numbers of cpus and numa nodes, we have to use as much virtual address space as possible for the vmalloc region. Otherwise we can get things like: PERCPU: max_distance=0x380001c10000 too large for vmalloc space 0xff00000000 So, once we select a value for PAGE_OFFSET, derive the size of the vmalloc region based upon that. Signed-off-by: David S. Miller Acked-by: Bob Picco

sparc64: Increase MAX_PHYS_ADDRESS_BITS to 53.

2014-10-05T23:53:40+00:00

Make sure, at compile time, that the kernel can properly support whatever MAX_PHYS_ADDRESS_BITS is defined to. On M7 chips, use a max_phys_bits value of 49. Based upon a patch by Bob Picco. Signed-off-by: David S. Miller Acked-by: Bob Picco

sparc64: Use kernel page tables for vmemmap.

2014-10-05T23:53:39+00:00

For sparse memory configurations, the vmemmap array behaves terribly and it takes up an inordinate amount of space in the BSS section of the kernel image unconditionally. Just build huge PMDs and look them up just like we do for TLB misses in the vmalloc area. Kernel BSS shrinks by about 2MB. Signed-off-by: David S. Miller Acked-by: Bob Picco