When searching a vmap area in the vmalloc space, we use (addr + size -
1) to check if the value is less than addr, which is an overflow. But
we assign (addr + size) to vmap_area->va_end.
So if we come across the below case:
(addr + size - 1) : not overflow
(addr + size) : overflow
we will assign an overflow value (e.g 0) to vmap_area->va_end, And this
will trigger BUG in __insert_vmap_area, causing system panic.
So using (addr + size) to check the overflow should be the correct
behaviour, not (addr + size - 1).
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Reported-by: Ghennadi Procopciuc <unix140@gmail.com>
Tested-by: Daniel Baluta <dbaluta@ixiacom.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should check the VM_UNITIALIZED flag in s_show(). If this flag is
set, that said, the vm_struct is not fully initialized. So it is
unnecessary to try to show the information contained in vm_struct.
We checked this flag in show_numa_info(), but I think it's better to
check it earlier.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
VM_UNLIST was used to indicate that the vm_struct is not listed in
vmlist.
But after commit 4341fa4547 ("mm, vmalloc: remove list management of
vmlist after initializing vmalloc"), the meaning of this flag changed.
It now means the vm_struct is not fully initialized. So renaming it to
VM_UNINITIALIZED seems more reasonable.
Also change clear_vm_unlist to clear_vm_uninitialized_flag.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use goto to jump to the fail label to give a failure message before
returning NULL. This makes the failure handling in this function
consistent.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Space in a vmap block that was once allocated is considered dirty and
not made available for allocation again before the whole block is
recycled. The result is that free space within a vmap block is always
contiguous.
So if a vmap block has enough free space for allocation, the allocation
is impossible to fail. Thus, the fragmented block purging was never
invoked from vb_alloc(). So remove this dead code.
[ Same patches also sent by:
Chanho Min <chanho.min@lge.com>
Johannes Weiner <hannes@cmpxchg.org>
but git doesn't do "multiple authors" ]
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now for insert_vmalloc_vm, it only calls the two functions:
- setup_vmalloc_vm: fill vm_struct and vmap_area instances
- clear_vm_unlist: clear VM_UNLIST bit in vm_struct->flags
So in __get_vm_area_node(), if VM_UNLIST bit unset in flags, that is the
else branch here, we don't need to clear VM_UNLIST bit for vm->flags since
this bit is obviously not set. That is to say, we could only call
setup_vmalloc_vm instead of insert_vmalloc_vm here. And then we could
even remove the if test here.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We want to allocate ELF note segment buffer on the 2nd kernel in vmalloc
space and remap it to user-space in order to reduce the risk that memory
allocation fails on system with huge number of CPUs and so with huge ELF
note segment that exceeds 11-order block size.
Although there's already remap_vmalloc_range for the purpose of
remapping vmalloc memory to user-space, we need to specify user-space
range via vma.
Mmap on /proc/vmcore needs to remap range across multiple objects, so
the interface that requires vma to cover full range is problematic.
This patch introduces remap_vmalloc_range_partial that receives user-space
range as a pair of base address and size and can be used for mmap on
/proc/vmcore case.
remap_vmalloc_range is rewritten using remap_vmalloc_range_partial.
[akpm@linux-foundation.org: use PAGE_ALIGNED()]
Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Lisa Mitchell <lisa.mitchell@hp.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, __find_vmap_area searches for the kernel VM area starting at
a given address. This patch changes this behavior so that it searches
for the kernel VM area to which the address belongs. This change is
needed by remap_vmalloc_range_partial to be introduced in later patch
that receives any position of kernel VM area as target address.
This patch changes the condition (addr > va->va_start) to the equivalent
(addr >= va->va_end) by taking advantage of the fact that each kernel VM
area is non-overlapping.
Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Lisa Mitchell <lisa.mitchell@hp.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull VFS updates from Al Viro,
Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).
7kloc removed.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
don't bother with deferred freeing of fdtables
proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
proc: Make the PROC_I() and PDE() macros internal to procfs
proc: Supply a function to remove a proc entry by PDE
take cgroup_open() and cpuset_open() to fs/proc/base.c
ppc: Clean up scanlog
ppc: Clean up rtas_flash driver somewhat
hostap: proc: Use remove_proc_subtree()
drm: proc: Use remove_proc_subtree()
drm: proc: Use minor->index to label things, not PDE->name
drm: Constify drm_proc_list[]
zoran: Don't print proc_dir_entry data in debug
reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
proc: Supply an accessor for getting the data from a PDE's parent
airo: Use remove_proc_subtree()
rtl8192u: Don't need to save device proc dir PDE
rtl8187se: Use a dir under /proc/net/r8180/
proc: Add proc_mkdir_data()
proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
proc: Move PDE_NET() to fs/proc/proc_net.c
...
Now, vmap_area_list is exported as VMCOREINFO for makedumpfile to get
the start address of vmalloc region (vmalloc_start). The address which
contains vmalloc_start value is represented as below:
vmap_area_list.next - OFFSET(vmap_area.list) + OFFSET(vmap_area.va_start)
However, both OFFSET(vmap_area.va_start) and OFFSET(vmap_area.list)
aren't exported as VMCOREINFO.
So this patch exports them externally with small cleanup.
[akpm@linux-foundation.org: vmalloc.h should include list.h for list_head]
Signed-off-by: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch is a preparatory step for removing vmlist entirely. For
above purpose, we change iterating a vmap_list codes to iterating a
vmap_area_list. It is somewhat trivial change, but just one thing
should be noticed.
Using vmap_area_list in vmallocinfo() introduce ordering problem in SMP
system. In s_show(), we retrieve some values from vm_struct.
vm_struct's values is not fully setup when va->vm is assigned. Full
setup is notified by removing VM_UNLIST flag without holding a lock.
When we see that VM_UNLIST is removed, it is not ensured that vm_struct
has proper values in view of other CPUs. So we need smp_[rw]mb for
ensuring that proper values is assigned when we see that VM_UNLIST is
removed.
Therefore, this patch not only change a iteration list, but also add a
appropriate smp_[rw]mb to right places.
Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch is a preparatory step for removing vmlist entirely. For
above purpose, we change iterating a vmap_list codes to iterating a
vmap_area_list. It is somewhat trivial change, but just one thing
should be noticed.
vmlist is lack of information about some areas in vmalloc address space.
For example, vm_map_ram() allocate area in vmalloc address space, but it
doesn't make a link with vmlist. To provide full information about
vmalloc address space is better idea, so we don't use va->vm and use
vmap_area directly. This makes get_vmalloc_info() more precise.
Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
