linux/mm/vmalloc.c, branch v3.2.38

mm: fix faulty initialization in vmalloc_init()

2012-06-10T13:41:46Z

commit dbda591d920b4c7692725b13e3f68ecb251e9080 upstream. The transfer of ->flags causes some of the static mapping virtual addresses to be prematurely freed (before the mapping is removed) because VM_LAZY_FREE gets "set" if tmp->flags has VM_IOREMAP set. This might cause subsequent vmalloc/ioremap calls to fail because it might allocate one of the freed virtual address ranges that aren't unmapped. va->flags has different types of flags from tmp->flags. If a region with VM_IOREMAP set is registered with vm_area_add_early(), it will be removed by __purge_vmap_area_lazy(). Fix vmalloc_init() to correctly initialize vmap_area for the given vm_struct. Also initialise va->vm. If it is not set, find_vm_area() for the early vm regions will always fail. Signed-off-by: KyongHo Cho Cc: "Olav Haugan" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings

mm/vmalloc.c: change void* into explict vm_struct*

2012-06-10T13:41:46Z

commit db1aecafef58b5dda39c4228debe2c845e4a27ab upstream. vmap_area->private is void* but we don't use the field for various purpose but use only for vm_struct. So change it to a vm_struct* with naming to improve for readability and type checking. Signed-off-by: Minchan Kim Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings

mm/vmalloc.c: remove static declaration of va from __get_vm_area_node

2011-12-20T18:25:04Z

Static storage is not required for the struct vmap_area in __get_vm_area_node. Removing "static" to store this variable on the stack instead. Signed-off-by: Kautuk Consul Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: vmalloc: check for page allocation failure before vmlist insertion

2011-12-09T15:50:29Z

Commit f5252e00 ("mm: avoid null pointer access in vm_struct via /proc/vmallocinfo") adds newly allocated vm_structs to the vmlist after it is fully initialised. Unfortunately, it did not check that __vmalloc_area_node() successfully populated the area. In the event of allocation failure, the vmalloc area is freed but the pointer to freed memory is inserted into the vmlist leading to a a crash later in get_vmalloc_info(). This patch adds a check for ____vmalloc_area_node() failure within __vmalloc_node_range. It does not use "goto fail" as in the previous error path as a warning was already displayed by __vmalloc_area_node() before it called vfree in its failure path. Credit goes to Luciano Chavez for doing all the real work of identifying exactly where the problem was. Signed-off-by: Mel Gorman Reported-by: Luciano Chavez Tested-by: Luciano Chavez Reviewed-by: Rik van Riel Acked-by: David Rientjes Cc: [3.1.x+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

xen: map foreign pages for shared rings by updating the PTEs directly

2011-11-16T17:13:08Z

When mapping a foreign page with xenbus_map_ring_valloc() with the GNTTABOP_map_grant_ref hypercall, set the GNTMAP_contains_pte flag and pass a pointer to the PTE (in init_mm). After the page is mapped, the usual fault mechanism can be used to update additional MMs. This allows the vmalloc_sync_all() to be removed from alloc_vm_area(). Signed-off-by: David Vrabel Acked-by: Andrew Morton [v1: Squashed fix by Michal for no-mmu case] Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Michal Simek

mm/vmalloc.c: report more vmalloc failures

2011-11-01T00:30:48Z

Some vmalloc failure paths do not report OOM conditions. Add warn_alloc_failed, which also does a dump_stack, to those failure paths. This allows more site specific vmalloc failure logging message printks to be removed. Signed-off-by: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: neaten warn_alloc_failed

2011-11-01T00:30:48Z

Add __attribute__((format (printf...) to the function to validate format and arguments. Use vsprintf extension %pV to avoid any possible message interleaving. Coalesce format string. Convert printks/pr_warning to pr_warn. [akpm@linux-foundation.org: use the __printf() macro] Signed-off-by: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: avoid null pointer access in vm_struct via /proc/vmallocinfo

2011-11-01T00:30:47Z

The /proc/vmallocinfo shows information about vmalloc allocations in vmlist that is a linklist of vm_struct. It, however, may access pages field of vm_struct where a page was not allocated. This results in a null pointer access and leads to a kernel panic. Why this happens: In __vmalloc_node_range() called from vmalloc(), newly allocated vm_struct is added to vmlist at __get_vm_area_node() and then, some fields of vm_struct such as nr_pages and pages are set at __vmalloc_area_node(). In other words, it is added to vmlist before it is fully initialized. At the same time, when the /proc/vmallocinfo is read, it accesses the pages field of vm_struct according to the nr_pages field at show_numa_info(). Thus, a null pointer access happens. The patch adds the newly allocated vm_struct to the vmlist *after* it is fully initialized. So, it can avoid accessing the pages field with unallocated page when show_numa_info() is called. Signed-off-by: Mitsuo Hayasaka Cc: Andrew Morton Cc: David Rientjes Cc: Namhyung Kim Cc: "Paul E. McKenney" Cc: Jeremy Fitzhardinge Cc: Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: sync vmalloc address space page tables in alloc_vm_area()

2011-09-15T01:09:38Z

Xen backend drivers (e.g., blkback and netback) would sometimes fail to map grant pages into the vmalloc address space allocated with alloc_vm_area(). The GNTTABOP_map_grant_ref would fail because Xen could not find the page (in the L2 table) containing the PTEs it needed to update. (XEN) mm.c:3846:d0 Could not find L1 PTE for address fbb42000 netback and blkback were making the hypercall from a kernel thread where task->active_mm != &init_mm and alloc_vm_area() was only updating the page tables for init_mm. The usual method of deferring the update to the page tables of other processes (i.e., after taking a fault) doesn't work as a fault cannot occur during the hypercall. This would work on some systems depending on what else was using vmalloc. Fix this by reverting ef691947d8a3 ("vmalloc: remove vmalloc_sync_all() from alloc_vm_area()") and add a comment to explain why it's needed. Signed-off-by: David Vrabel Cc: Jeremy Fitzhardinge Cc: Konrad Rzeszutek Wilk Cc: Ian Campbell Cc: Keir Fraser Cc: [3.0.x] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: fix wrong vmap address calculations with odd NR_CPUS values

2011-08-14T19:32:52Z

Commit db64fe02258f ("mm: rewrite vmap layer") introduced code that does address calculations under the assumption that VMAP_BLOCK_SIZE is a power of two. However, this might not be true if CONFIG_NR_CPUS is not set to a power of two. Wrong vmap_block index/offset values could lead to memory corruption. However, this has never been observed in practice (or never been diagnosed correctly); what caught this was the BUG_ON in vb_alloc() that checks for inconsistent vmap_block indices. To fix this, ensure that VMAP_BLOCK_SIZE always is a power of two. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=31572 Reported-by: Pavel Kysilka Reported-by: Matias A. Fonzo Signed-off-by: Clemens Ladisch Signed-off-by: Stefan Richter Cc: Nick Piggin Cc: Jeremy Fitzhardinge Cc: Krzysztof Helt Cc: Andrew Morton Cc: 2.6.28+ Signed-off-by: Linus Torvalds