android_kernel_sony_sdm845/include/asm-generic
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Toshi Kani 9c7f7bdb19 mm/vmalloc: add interfaces to free unmapped page table
commit b6bdb7517c3d3f41f20e5c2948d6bc3f8897394e upstream.

On architectures with CONFIG_HAVE_ARCH_HUGE_VMAP set, ioremap() may
create pud/pmd mappings.  A kernel panic was observed on arm64 systems
with Cortex-A75 in the following steps as described by Hanjun Guo.

 1. ioremap a 4K size, valid page table will build,
 2. iounmap it, pte0 will set to 0;
 3. ioremap the same address with 2M size, pgd/pmd is unchanged,
    then set the a new value for pmd;
 4. pte0 is leaked;
 5. CPU may meet exception because the old pmd is still in TLB,
    which will lead to kernel panic.

This panic is not reproducible on x86.  INVLPG, called from iounmap,
purges all levels of entries associated with purged address on x86.  x86
still has memory leak.

The patch changes the ioremap path to free unmapped page table(s) since
doing so in the unmap path has the following issues:

 - The iounmap() path is shared with vunmap(). Since vmap() only
   supports pte mappings, making vunmap() to free a pte page is an
   overhead for regular vmap users as they do not need a pte page freed
   up.

 - Checking if all entries in a pte page are cleared in the unmap path
   is racy, and serializing this check is expensive.

 - The unmap path calls free_vmap_area_noflush() to do lazy TLB purges.
   Clearing a pud/pmd entry before the lazy TLB purges needs extra TLB
   purge.

Add two interfaces, pud_free_pmd_page() and pmd_free_pte_page(), which
clear a given pud/pmd entry and free up a page for the lower level
entries.

This patch implements their stub functions on x86 and arm64, which work
as workaround.

[akpm@linux-foundation.org: fix typo in pmd_free_pte_page() stub]
Link: http://lkml.kernel.org/r/20180314180155.19492-2-toshi.kani@hpe.com
Fixes: e61ce6ade4 ("mm: change ioremap to set up huge I/O mappings")
Reported-by: Lei Li <lious.lilei@hisilicon.com>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Wang Xuefeng <wxf.wang@hisilicon.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Chintan Pandya <cpandya@codeaurora.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-28 18:39:21 +02:00
..
bitops bitops: Do not default to __clear_bit() for __clear_bit_unlock() 2016-03-21 10:50:48 +01:00
4level-fixup.h mm, asm-generic: define PUD_SHIFT in <asm-generic/4level-fixup.h> 2015-02-11 17:06:03 -08:00
asm-offsets.h asm-generic: Add common asm-offsets.h 2015-06-23 13:35:49 +09:00
asm-prototypes.h asm-prototypes: Clear any CPP defines before declaring the functions 2017-01-12 11:39:07 +01:00
atomic-long.h locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API 2016-07-07 09:16:20 +02:00
atomic.h locking/atomic: Remove linux/atomic.h:atomic_fetch_or() 2016-06-16 10:48:32 +02:00
atomic64.h locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() 2016-06-16 10:48:32 +02:00
audit_change_attr.h audit: Modify a set of system calls in audit class definitions 2014-01-17 17:01:46 -05:00
audit_dir_write.h audit: support the "standard" <asm-generic/unistd.h> 2011-05-04 14:41:28 -04:00
audit_read.h audit: support the "standard" <asm-generic/unistd.h> 2011-05-04 14:41:28 -04:00
audit_signal.h
audit_write.h audit: Modify a set of system calls in audit class definitions 2014-01-17 17:01:46 -05:00
barrier.h locking/spinlock, arch: Update and fix spin_unlock_wait() implementations 2016-06-14 11:55:15 +02:00
bitops.h arch: Prepare for smp_mb__{before,after}_atomic() 2014-04-18 11:40:30 +02:00
bitsperlong.h UAPI: (Scripted) Disintegrate include/asm-generic 2012-10-04 18:20:15 +01:00
bug.h asm-generic changes for 4.6 2016-03-24 23:13:48 -07:00
bugs.h
cache.h
cacheflush.h asm-generic/cacheflush.h: flush icache when copying to user pages 2011-05-25 08:39:37 -07:00
checksum.h ipv4: Update parameters for csum_tcpudp_magic to their original types 2016-03-13 23:55:13 -04:00
clkdev.h asm-generic: COMMON_CLK defines __clk_{get,put} 2014-09-25 18:00:45 -07:00
cmpxchg-local.h LLVMLinux: Remove warning about returning an uninitialized variable 2014-04-09 13:44:35 -07:00
cmpxchg.h asm-generic: cmpxchg: avoid warnings from macro-ized cmpxchg() implementations 2015-10-15 00:21:13 +02:00
cputime.h cputime: Generic on-demand virtual cputime accounting 2013-01-27 19:23:27 +01:00
cputime_jiffies.h sched, time: Fix build error with 64 bit cputime_t on 32 bit systems 2014-10-03 05:46:55 +02:00
cputime_nsecs.h sched/cputime: Count actually elapsed irq & softirq time 2016-07-14 10:42:34 +02:00
current.h
delay.h asm-generic: delay.h fix udelay and ndelay for 8 bit args 2011-07-22 18:45:33 +02:00
device.h
div64.h __div64_32(): make it overridable at compile time 2015-11-16 14:42:12 -05:00
dma-contiguous.h asm-generic: Add dma-contiguous.h 2014-09-22 13:35:51 +02:00
dma.h
early_ioremap.h Merge branch 'akpm' (patches from Andrew) 2015-09-08 17:52:23 -07:00
emergency-restart.h
exec.h Split arch_align_stack() out from asm-generic/system.h 2012-03-28 18:30:03 +01:00
export.h Revert "default exported asm symbols to zero" 2016-12-07 08:39:00 -08:00
fb.h
fixmap.h asm-generic: Fix local variable shadow in __set_fixmap_offset 2016-02-16 15:10:44 +00:00
ftrace.h asm-generic headers: add ftrace.h 2011-03-17 09:19:04 +08:00
futex.h asm-generic/futex: Re-enable preemption in futex_atomic_cmpxchg_inatomic() 2016-04-21 11:06:09 +02:00
getorder.h bitops: Add missing parentheses to new get_order macro 2012-02-24 10:39:27 -08:00
gpio.h gpio: allow setting ARCH_NR_GPIOS from Kconfig 2016-02-19 00:22:54 +01:00
hardirq.h
hugetlb.h mm: Fix generic hugetlb pte check return type. 2013-10-02 20:02:35 -04:00
hw_irq.h
ide_iops.h
int-ll64.h UAPI: (Scripted) Disintegrate include/asm-generic 2012-10-04 18:20:15 +01:00
io.h asm-generic/io.h: add io{read,write}64 accessors 2016-05-31 16:41:50 +08:00
ioctl.h include/asm-generic/ioctl.h: fix _IOC_TYPECHECK sparse error 2014-06-06 16:08:13 -07:00
iomap.h asm-generic/io.h: add io{read,write}64 accessors 2016-05-31 16:41:50 +08:00
irq.h
irq_regs.h
irq_work.h irq_work: Introduce arch_irq_work_has_interrupt() 2014-09-13 18:38:07 +02:00
irqflags.h
Kbuild.asm UAPI: Set up uapi/asm/Kbuild.asm 2012-10-02 18:01:56 +01:00
kdebug.h
kmap_types.h asm-generic: remove km_type definitions 2012-07-24 15:27:30 +08:00
kvm_para.h KVM: add kvm_para_available to asm-generic/kvm_para.h 2013-06-05 13:21:29 +03:00
linkage.h
local.h atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
local64.h atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
mcs_spinlock.h locking/mcs: Allow architecture specific asm files to be used for contended case 2014-02-09 21:18:52 +01:00
memory_model.h mm: add PHYS_PFN, use it in __phys_to_pfn() 2016-01-14 16:00:49 -08:00
mm-arch-hooks.h mm: clean up per architecture MM hook header files 2015-07-17 16:39:53 -07:00
mm_hooks.h mm/core, x86/mm/pkeys: Differentiate instruction fetches 2016-02-18 19:46:29 +01:00
mmu.h asm-generic/mmu.h: Add support for FDPIC 2012-12-09 23:14:14 +01:00
mmu_context.h asm-generic: Remove asm-generic arch_bprm_mm_init() 2014-11-22 21:52:08 +01:00
module.h Make most arch asm/module.h files use asm-generic/module.h 2012-09-28 14:31:03 +09:30
msi.h asm-generic: Add msi.h 2014-11-23 13:01:47 +01:00
mutex-dec.h locking/mutex: Optimize mutex_trylock() fast-path 2016-06-08 15:17:01 +02:00
mutex-null.h arch: Make __mutex_fastpath_lock_retval return whether fastpath succeeded or not 2013-06-26 12:10:55 +02:00
mutex-xchg.h locking/mutex: Optimize mutex_trylock() fast-path 2016-06-08 15:17:01 +02:00
mutex.h
page.h asm-generic: page.h: Remove useless get_user_page and free_user_page 2016-02-26 15:24:55 +01:00
param.h UAPI: (Scripted) Disintegrate include/asm-generic 2012-10-04 18:20:15 +01:00
parport.h include: remove __dev* attributes. 2013-01-03 15:57:16 -08:00
pci.h PCI: Remove unused pcibios_select_root() (again) 2015-06-08 07:56:21 -05:00
pci_iomap.h PCI: Add pci_iomap_wc() variants 2015-08-25 09:59:45 +02:00
percpu.h percpu: make this_cpu_generic_read() atomic w.r.t. interrupts 2017-10-12 11:51:23 +02:00
pgalloc.h
pgtable-nopmd.h
pgtable-nopud.h
pgtable.h mm/vmalloc: add interfaces to free unmapped page table 2018-03-28 18:39:21 +02:00
preempt.h sched/preempt: Fix preempt_count manipulations 2016-05-17 12:24:21 +02:00
ptrace.h asm-generic/ptrace.h: start a common low level ptrace helper 2011-05-26 17:12:36 -07:00
qrwlock.h locking/qrwlock: Fix write unlock bug on big endian systems 2016-08-10 14:13:27 +02:00
qrwlock_types.h locking/qrwlock: Rename ->lock to ->wait_lock 2015-09-18 09:27:29 +02:00
qspinlock.h locking/qspinlock: Use atomic_sub_return_release() in queued_spin_unlock() 2016-06-08 15:17:01 +02:00
qspinlock_types.h locking/qspinlock: Move __ARCH_SPIN_LOCK_UNLOCKED to qspinlock_types.h 2016-02-29 10:02:43 +01:00
resource.h asm-generic: remove _STK_LIM_MAX 2014-05-15 00:32:09 +01:00
rwsem.h locking/rwsem: Remove rwsem_atomic_add() and rwsem_atomic_update() 2016-06-08 15:16:59 +02:00
seccomp.h seccomp: Get compat syscalls from asm-generic header 2016-05-13 14:02:00 +02:00
sections.h mm: kmemleak: scan .data.ro_after_init 2016-11-11 08:12:37 -08:00
segment.h
serial.h
siginfo.h SIGNAL: Move generic copy_siginfo() to signal.h 2016-05-13 14:02:10 +02:00
signal.h unify default ptrace_signal_deliver 2012-11-29 00:01:23 -05:00
simd.h crypto: create generic version of ablk_helper 2013-09-24 06:02:24 +10:00
sizes.h ARM: 7430/1: sizes.h: move from asm-generic to <linux/sizes.h> 2012-06-28 17:14:34 +01:00
spinlock.h
statfs.h UAPI: (Scripted) Disintegrate include/asm-generic 2012-10-04 18:20:15 +01:00
string.h
switch_to.h Split the switch_to() wrapper out of asm-generic/system.h 2012-03-28 18:30:03 +01:00
syscall.h syscall.h: fix doc text for syscall_get_arch() 2014-09-23 16:20:00 -04:00
syscalls.h burying unused conditionals 2013-02-14 09:21:15 -05:00
termios-base.h
termios.h UAPI: (Scripted) Disintegrate include/asm-generic 2012-10-04 18:20:15 +01:00
timex.h
tlb.h mm/mmu_gather: track page size with mmu gather and force flush if page size change 2016-07-26 16:19:19 -07:00
tlbflush.h BUG: headers with BUG/BUG_ON etc. need linux/bug.h 2012-03-04 17:54:34 -05:00
topology.h cpumask: fix spurious cpumask_of_node() on non-NUMA multi-node configs 2017-09-07 08:35:40 +02:00
trace_clock.h tracing,x86: Add a TSC trace_clock 2012-11-13 15:48:27 -05:00
uaccess-unaligned.h
uaccess.h exceptions: detritus removal 2016-09-27 21:15:14 -04:00
unaligned.h asm-generic: allow generic unaligned access if the arch supports it 2014-05-08 10:22:23 +02:00
unistd.h We get rid of the general module prefix confusion with a binary config option, 2013-05-05 10:58:06 -07:00
user.h asm-generic/user.h: Fix spelling in comment 2011-03-01 15:49:39 +01:00
vga.h
vmlinux.lds.h kaiser: cleanups while trying for gold link 2018-01-05 15:46:33 +01:00
vtime.h include/asm-generic/vtime.h: avoid zero-length file 2013-09-30 14:31:02 -07:00
word-at-a-time.h Make asm/word-at-a-time.h available on all architectures 2015-07-08 16:41:55 -04:00
xor.h asm-generic: xor: mark static functions as __maybe_unused 2012-10-03 21:21:06 +02:00