linux-stable.git/arch/arm64/include, branch v4.0.2

arm64: errata: add workaround for cortex-a53 erratum #845719

2015-05-06T20:03:55+00:00

commit 905e8c5dcaa147163672b06fe9dcb5abaacbc711 upstream.

When running a compat (AArch32) userspace on Cortex-A53, a load at EL0
from a virtual address that matches the bottom 32 bits of the virtual
address used by a recent load at (AArch64) EL1 might return incorrect
data.

This patch works around the issue by writing to the contextidr_el1
register on the exception return path when returning to a 32-bit task.
This workaround is patched in at runtime based on the MIDR value of the
processor.

Reviewed-by: Marc Zyngier 
Tested-by: Mark Rutland 
Signed-off-by: Will Deacon 
Signed-off-by: Kevin Hilman 
Signed-off-by: Greg Kroah-Hartman

arm64: apply alternatives for !SMP kernels

2015-05-06T20:03:54+00:00

commit 137650aad96c9594683445e41afa8ac5a2097520 upstream.

Currently we only perform alternative patching for kernels built with
CONFIG_SMP, as we call apply_alternatives_all() in smp.c, which is only
built for CONFIG_SMP. Thus !SMP kernels may not have necessary
alternatives patched in.

This patch ensures that we call apply_alternatives_all() once all CPUs
are booted, even for !SMP kernels, by having the smp_init_cpus() stub
call this for !SMP kernels via up_late_init. A new wrapper,
do_post_cpus_up_work, is added so we can hook other calls here later
(e.g. boot mode logging).

Cc: Andre Przywara 
Cc: Catalin Marinas 
Fixes: e039ee4ee3fcf174 ("arm64: add alternative runtime patching")
Tested-by: Ard Biesheuvel 
Reviewed-by: Ard Biesheuvel 
Signed-off-by: Mark Rutland 
Signed-off-by: Will Deacon 
Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: check IRQ number on userland injection

2015-05-06T20:03:40+00:00

commit fd1d0ddf2ae92fb3df42ed476939861806c5d785 upstream.

When userland injects a SPI via the KVM_IRQ_LINE ioctl we currently
only check it against a fixed limit, which historically is set
to 127. With the new dynamic IRQ allocation the effective limit may
actually be smaller (64).
So when now a malicious or buggy userland injects a SPI in that
range, we spill over on our VGIC bitmaps and bytemaps memory.
I could trigger a host kernel NULL pointer dereference with current
mainline by injecting some bogus IRQ number from a hacked kvmtool:
-----------------
....
DEBUG: kvm_vgic_inject_irq(kvm, cpu=0, irq=114, level=1)
DEBUG: vgic_update_irq_pending(kvm, cpu=0, irq=114, level=1)
DEBUG: IRQ #114 still in the game, writing to bytemap now...
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = ffffffc07652e000
[00000000] *pgd=00000000f658b003, *pud=00000000f658b003, *pmd=0000000000000000
Internal error: Oops: 96000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 1053 Comm: lkvm-msi-irqinj Not tainted 4.0.0-rc7+ #3027
Hardware name: FVP Base (DT)
task: ffffffc0774e9680 ti: ffffffc0765a8000 task.ti: ffffffc0765a8000
PC is at kvm_vgic_inject_irq+0x234/0x310
LR is at kvm_vgic_inject_irq+0x30c/0x310
pc : [] lr : [] pstate: 80000145
.....

So this patch fixes this by checking the SPI number against the
actual limit. Also we remove the former legacy hard limit of
127 in the ioctl code.

Signed-off-by: Andre Przywara 
Reviewed-by: Christoffer Dall 
[maz: wrap KVM_ARM_IRQ_GIC_MAX with #ifndef __KERNEL__,
as suggested by Christopher Covington]
Signed-off-by: Marc Zyngier 
Signed-off-by: Greg Kroah-Hartman

arm64: percpu: Make this_cpu accessors pre-empt safe

2015-03-24T18:02:55+00:00

this_cpu operations were implemented for arm64 in:
 5284e1b arm64: xchg: Implement cmpxchg_double
 f97fc81 arm64: percpu: Implement this_cpu operations

Unfortunately, it is possible for pre-emption to take place between
address generation and data access. This can lead to cases where data
is being manipulated by this_cpu for a different CPU than it was
called on. Which effectively breaks the spec.

This patch disables pre-emption for the this_cpu operations
guaranteeing that address generation and data manipulation take place
without a pre-emption in-between.

Fixes: 5284e1b4bc8a ("arm64: xchg: Implement cmpxchg_double")
Fixes: f97fc810798c ("arm64: percpu: Implement this_cpu operations")
Reported-by: Mark Rutland 
Acked-by: Will Deacon 
Signed-off-by: Steve Capper 
[catalin.marinas@arm.com: remove space after type cast]
Signed-off-by: Catalin Marinas

arm64: Use the reserved TTBR0 if context switching to the init_mm

2015-03-23T18:42:23+00:00

The idle_task_exit() function may call switch_mm() with next ==
&init_mm. On arm64, init_mm.pgd cannot be used for user mappings, so
this patch simply sets the reserved TTBR0.

Cc: 
Reported-by: Jon Medhurst (Tixy) 
Tested-by: Jon Medhurst (Tixy) 
Signed-off-by: Catalin Marinas

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2015-03-21T17:24:10+00:00

Pull arm64 fixes from Catalin Marinas:

 - mm switching fix where the kernel pgd ends up in the user TTBR0 after
   returning from an EFI run-time services call

 - fix __GFP_ZERO handling for atomic pool and CMA DMA allocations (the
   generic code does get the gfp flags, so it's left with the arch code
   to memzero accordingly)

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Honor __GFP_ZERO in dma allocations
  arm64: efi: don't restore TTBR0 if active_mm points at init_mm

arm64: efi: don't restore TTBR0 if active_mm points at init_mm

2015-03-20T17:05:16+00:00

init_mm isn't a normal mm: it has swapper_pg_dir as its pgd (which
contains kernel mappings) and is used as the active_mm for the idle
thread.

When restoring the pgd after an EFI call, we write current->active_mm
into TTBR0. If the current task is actually the idle thread (e.g. when
initialising the EFI RTC before entering userspace), then the TLB can
erroneously populate itself with junk global entries as a result of
speculative table walks.

When we do eventually return to userspace, the task can end up hitting
these junk mappings leading to lockups, corruption or crashes.

This patch fixes the problem in the same way as the CPU suspend code by
ensuring that we never switch to the init_mm in efi_set_pgd and instead
point TTBR0 at the zero page. A check is also added to cpu_switch_mm to
BUG if we get passed swapper_pg_dir.

Reviewed-by: Ard Biesheuvel 
Fixes: f3cdfd239da5 ("arm64/efi: move SetVirtualAddressMap() to UEFI stub")
Signed-off-by: Will Deacon 
Signed-off-by: Catalin Marinas

Merge git://git.kernel.org/pub/scm/virt/kvm/kvm

2015-03-17T17:31:36+00:00

Pull kvm fixes from Marcelo Tosatti:
 "KVM bug fixes (ARM and x86)"

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  arm/arm64: KVM: Keep elrsr/aisr in sync with software model
  KVM: VMX: Set msr bitmap correctly if vcpu is in guest mode
  arm/arm64: KVM: fix missing unlock on error in kvm_vgic_create()
  kvm: x86: i8259: return initialized data on invalid-size read
  arm64: KVM: Fix outdated comment about VTCR_EL2.PS
  arm64: KVM: Do not use pgd_index to index stage-2 pgd
  arm64: KVM: Fix stage-2 PGD allocation to have per-page refcounting
  kvm: move advertising of KVM_CAP_IRQFD to common code

arm64: Invalidate the TLB corresponding to intermediate page table levels

2015-03-14T10:48:30+00:00

The ARM architecture allows the caching of intermediate page table
levels and page table freeing requires a sequence like:

	pmd_clear()
	TLB invalidation
	pte page freeing

With commit 5e5f6dc10546 (arm64: mm: enable HAVE_RCU_TABLE_FREE logic),
the page table freeing batching was moved from tlb_remove_page() to
tlb_remove_table(). The former takes care of TLB invalidation as this is
also shared with pte clearing and page cache page freeing. The latter,
however, does not invalidate the TLBs for intermediate page table levels
as it probably relies on the architecture code to do it if required.
When the mm->mm_users < 2, tlb_remove_table() does not do any batching
and page table pages are freed before tlb_finish_mmu() which performs
the actual TLB invalidation.

This patch introduces __tlb_flush_pgtable() for arm64 and calls it from
the {pte,pmd,pud}_free_tlb() directly without relying on deferred page
table freeing.

Fixes: 5e5f6dc10546 arm64: mm: enable HAVE_RCU_TABLE_FREE logic
Reported-by: Jon Masters 
Tested-by: Jon Masters 
Tested-by: Steve Capper 
Signed-off-by: Catalin Marinas

arm64: KVM: Fix outdated comment about VTCR_EL2.PS

2015-03-11T13:24:37+00:00

Commit 87366d8cf7b3 ("arm64: Add boot time configuration of
Intermediate Physical Address size") removed the hardcoded setting
of VTCR_EL2.PS to use ID_AA64MMFR0_EL1.PARange instead, but didn't
remove the (now rather misleading) comment.

Fix the comments to match reality (at least for the next few minutes).

Acked-by: Christoffer Dall 
Signed-off-by: Marc Zyngier 
Signed-off-by: Christoffer Dall