BMC/Intel-BMC/linux.git/mm/cma.c, branch v4.7.2

mm/cma: silence warnings due to max() usage

2016-05-27T21:49:37+00:00

pageblock_order can be (at least) an unsigned int or an unsigned long depending on the kernel config and architecture, so use max_t(unsigned long, ...) when comparing it. fixes these warnings: In file included from include/asm-generic/bug.h:13:0, from arch/powerpc/include/asm/bug.h:127, from include/linux/bug.h:4, from include/linux/mmdebug.h:4, from include/linux/mm.h:8, from include/linux/memblock.h:18, from mm/cma.c:28: mm/cma.c: In function 'cma_init_reserved_mem': include/linux/kernel.h:748:17: warning: comparison of distinct pointer types lacks a cast (void) (&_max1 == &_max2); ^ mm/cma.c:186:27: note: in expansion of macro 'max' alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); ^ mm/cma.c: In function 'cma_declare_contiguous': include/linux/kernel.h:748:17: warning: comparison of distinct pointer types lacks a cast (void) (&_max1 == &_max2); ^ include/linux/kernel.h:747:9: note: in definition of macro 'max' typeof(y) _max2 = (y); ^ mm/cma.c:270:29: note: in expansion of macro 'max' (phys_addr_t)PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order)); ^ include/linux/kernel.h:748:17: warning: comparison of distinct pointer types lacks a cast (void) (&_max1 == &_max2); ^ include/linux/kernel.h:747:21: note: in definition of macro 'max' typeof(y) _max2 = (y); ^ mm/cma.c:270:29: note: in expansion of macro 'max' (phys_addr_t)PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order)); ^ [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20160526150748.5be38a4f@canb.auug.org.au Signed-off-by: Stephen Rothwell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/cma.c: suppress warning

2015-11-06T03:34:48+00:00

mm/cma.c: In function 'cma_alloc': mm/cma.c:366: warning: 'pfn' may be used uninitialized in this function The patch actually improves the tracing a bit: if alloc_contig_range() fails, tracing will display the offending pfn rather than -1. Cc: Stefan Strogin Cc: Michal Nazarewicz Cc: Marek Szyprowski Cc: Laurent Pinchart Cc: Thierry Reding Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: cma: fix incorrect type conversion for size during dma allocation

2015-10-23T08:55:10+00:00

This was found during userspace fuzzing test when a large size dma cma allocation is made by driver(like ion) through userspace. show_stack+0x10/0x1c dump_stack+0x74/0xc8 kasan_report_error+0x2b0/0x408 kasan_report+0x34/0x40 __asan_storeN+0x15c/0x168 memset+0x20/0x44 __dma_alloc_coherent+0x114/0x18c Signed-off-by: Rohit Vaswani Acked-by: Greg Kroah-Hartman Cc: Marek Szyprowski Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

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

mm/cma.c: fix typos in comments

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

Signed-off-by: Shailendra Verma Acked-by: Michal Nazarewicz Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: cma: add trace events for CMA allocations and freeings

2015-04-15T23:35:19+00:00

Add trace events for cma_alloc() and cma_release(). The cma_alloc tracepoint is used both for successful and failed allocations, in case of allocation failure pfn=-1UL is stored and printed. Signed-off-by: Stefan Strogin Cc: Ingo Molnar Cc: Steven Rostedt Cc: Joonsoo Kim Cc: Michal Nazarewicz Cc: Marek Szyprowski Cc: Laurent Pinchart Cc: Thierry Reding Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: cma: constify and use correct signness in mm/cma.c

2015-04-14T23:49:04+00:00

Constify function parameters and use correct signness where needed. Signed-off-by: Sasha Levin Cc: Michal Nazarewicz Cc: Marek Szyprowski Cc: Joonsoo Kim Cc: Laurent Pinchart Acked-by: Gregory Fong Cc: Pintu Kumar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: cma: allocation trigger

2015-04-14T23:49:00+00:00

Provides a userspace interface to trigger a CMA allocation. Usage: echo [pages] > alloc This would provide testing/fuzzing access to the CMA allocation paths. Signed-off-by: Sasha Levin Acked-by: Joonsoo Kim Cc: Marek Szyprowski Cc: Laura Abbott Cc: Konrad Rzeszutek Wilk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: cma: debugfs interface

2015-04-14T23:49:00+00:00

I've noticed that there is no interfaces exposed by CMA which would let me fuzz what's going on in there. This small patchset exposes some information out to userspace, plus adds the ability to trigger allocation and freeing from userspace. This patch (of 3): Implement a simple debugfs interface to expose information about CMA areas in the system. Useful for testing/sanity checks for CMA since it was impossible to previously retrieve this information in userspace. Signed-off-by: Sasha Levin Acked-by: Joonsoo Kim Cc: Marek Szyprowski Cc: Laura Abbott Cc: Konrad Rzeszutek Wilk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: cma: fix CMA aligned offset calculation

2015-03-13T01:46:07+00:00

The CMA aligned offset calculation is incorrect for non-zero order_per_bit values. For example, if cma->order_per_bit=1, cma->base_pfn= 0x2f800000 and align_order=12, the function returns a value of 0x17c00 instead of 0x400. This patch fixes the CMA aligned offset calculation. The previous calculation was wrong and would return too-large values for the offset, so that when cma_alloc looks for free pages in the bitmap with the requested alignment > order_per_bit, it starts too far into the bitmap and so CMA allocations will fail despite there actually being plenty of free pages remaining. It will also probably have the wrong alignment. With this change, we will get the correct offset into the bitmap. One affected user is powerpc KVM, which has kvm_cma->order_per_bit set to KVM_CMA_CHUNK_ORDER - PAGE_SHIFT, or 18 - 12 = 6. [gregory.0xf0@gmail.com: changelog additions] Signed-off-by: Danesh Petigara Reviewed-by: Gregory Fong Acked-by: Michal Nazarewicz Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds