commit 92e788b749 upstream.
As previously reported, some userspace applications depend on bogomips
showed by /proc/cpuinfo. Although there is much less legacy impact on
aarch64 than arm, it does break libvirt.
This patch reverts commit 326b16db9f ("arm64: delay: don't bother
reporting bogomips in /proc/cpuinfo"), but with some tweak due to
context change and without the pr_info().
Fixes: 326b16db9f ("arm64: delay: don't bother reporting bogomips in /proc/cpuinfo")
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
[ luis: backported to 3.16:
- file rename: cpuinfo.c -> setup.c
- linux/delay.h is already included
- adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 581b7f158f upstream.
There appears to be no formal statement of what pv_irq_ops.save_fl() is
supposed to return precisely. Native returns the full flags, while lguest and
Xen only return the Interrupt Flag, and both have comments by the
implementations stating that only the Interrupt Flag is looked at. This may
have been true when initially implemented, but no longer is.
To make matters worse, the Xen PVOP leaves the upper bits undefined, making
the BUG_ON() undefined behaviour. Experimentally, this now trips for 32bit PV
guests on Broadwell hardware. The BUG_ON() is consistent for an individual
build, but not consistent for all builds. It has also been a sitting timebomb
since SMAP support was introduced.
Use native_save_fl() instead, which will obtain an accurate view of the AC
flag.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Tested-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <lguest@lists.ozlabs.org>
Cc: Xen-devel <xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/1433323874-6927-1-git-send-email-andrew.cooper3@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit de818bd452 upstream.
The function graph tracer adds instrumentation that is required to trace
both entry and exit of a function. In particular the function graph
tracer updates the "return address" of a function in order to insert
a trace callback on function exit.
Kernel power management functions like cpu_suspend() are called
upon power down entry with functions called "finishers" that are in turn
called to trigger the power down sequence but they may not return to the
kernel through the normal return path.
When the core resumes from low-power it returns to the cpu_suspend()
function through the cpu_resume path, which leaves the trace stack frame
set-up by the function tracer in an incosistent state upon return to the
kernel when tracing is enabled.
This patch fixes the issue by pausing/resuming the function graph
tracer on the thread executing cpu_suspend() (ie the function call that
subsequently triggers the "suspend finishers"), so that the function graph
tracer state is kept consistent across functions that enter power down
states and never return by effectively disabling graph tracer while they
are executing.
Fixes: 819e50e25d ("arm64: Add ftrace support")
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit ab6b529475 upstream.
(This should have gone to LKML originally. Sorry for the extra
noise, folks on the cc.)
Background:
Signal frames on x86 have two formats:
1. For 32-bit executables (whether on a real 32-bit kernel or
under 32-bit emulation on a 64-bit kernel) we have a
'fpregset_t' that includes the "FSAVE" registers.
2. For 64-bit executables (on 64-bit kernels obviously), the
'fpregset_t' is smaller and does not contain the "FSAVE"
state.
When creating the signal frame, we have to be aware of whether
we are running a 32 or 64-bit executable so we create the
correct format signal frame.
Problem:
save_xstate_epilog() uses 'fx_sw_reserved_ia32' whenever it is
called for a 32-bit executable. This is for real 32-bit and
ia32 emulation.
But, fpu__init_prepare_fx_sw_frame() only initializes
'fx_sw_reserved_ia32' when emulation is enabled, *NOT* for real
32-bit kernels.
This leads to really wierd situations where 32-bit programs
lose their extended state when returning from a signal handler.
The kernel copies the uninitialized (zero) 'fx_sw_reserved_ia32'
out to userspace in save_xstate_epilog(). But when returning
from the signal, the kernel errors out in check_for_xstate()
when it does not see FP_XSTATE_MAGIC1 present (because it was
zeroed). This leads to the FPU/XSAVE state being initialized.
For MPX, this leads to the most permissive state and means we
silently lose bounds violations. I think this would also mean
that we could lose *ANY* FPU/SSE/AVX state. I'm not sure why
no one has spotted this bug.
I believe this was broken by:
72a671ced6 ("x86, fpu: Unify signal handling code paths for x86 and x86_64 kernels")
way back in 2012.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@sr71.net
Cc: fenghua.yu@intel.com
Cc: yu-cheng.yu@intel.com
Link: http://lkml.kernel.org/r/20151111002354.A0799571@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[ luis: backported to 3.16:
- file and function rename:
* arch/x86/kernel/fpu/signal.c -> arch/x86/kernel/xsave.c
* fpu__init_prepare_fx_sw_frame() -> prepare_fx_sw_frame()
- use 'i387_fsave_struct' instead of 'fregs_state'
- adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 54c09889bf upstream.
The z2 machine calls pxa27x_set_pwrmode() in order to power off
the machine, but this function gets discarded early at boot because
it is marked __init, as pointed out by kbuild:
WARNING: vmlinux.o(.text+0x145c4): Section mismatch in reference from the function z2_power_off() to the function .init.text:pxa27x_set_pwrmode()
The function z2_power_off() references
the function __init pxa27x_set_pwrmode().
This is often because z2_power_off lacks a __init
annotation or the annotation of pxa27x_set_pwrmode is wrong.
This removes the __init section modifier to fix rebooting and the
build error.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: ba4a90a6d8 ("ARM: pxa/z2: fix building error of pxa27x_cpu_suspend() no longer available")
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit cbdb967af3 upstream.
This is needed to avoid the possibility that the guest triggers
an infinite stream of #DB exceptions (CVE-2015-8104).
VMX is not affected: because it does not save DR6 in the VMCS,
it already intercepts #DB unconditionally.
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 54a20552e1 upstream.
It was found that a guest can DoS a host by triggering an infinite
stream of "alignment check" (#AC) exceptions. This causes the
microcode to enter an infinite loop where the core never receives
another interrupt. The host kernel panics pretty quickly due to the
effects (CVE-2015-5307).
Signed-off-by: Eric Northup <digitaleric@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit c9cdd085bb upstream.
Defining XE, XM and VE vector numbers.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 04633df0c4 upstream.
When we get loaded by a 64-bit bootloader, kernel entry point is
startup_64 in head_64.S. We don't trust any and all bootloaders because
some will fiddle with CPU configuration so we go ahead and massage each
CPU into sanity again.
For example, some dell BIOSes have this XD disable feature which set
IA32_MISC_ENABLE[34] and disable NX. This might be some dumb workaround
for other OSes but Linux sure doesn't need it.
A similar thing is present in the Surface 3 firmware - see
https://bugzilla.kernel.org/show_bug.cgi?id=106051 - which sets this bit
only on the BSP:
# rdmsr -a 0x1a0
400850089
850089
850089
850089
I know, right?!
There's not even an off switch in there.
So fix all those cases by sanitizing the 64-bit entry point too. For
that, make verify_cpu() callable in 64-bit mode also.
Requested-and-debugged-by: "H. Peter Anvin" <hpa@zytor.com>
Reported-and-tested-by: Bastien Nocera <bugzilla@hadess.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1446739076-21303-1-git-send-email-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 68accac392 upstream.
The commit f5f3497cad extended the low identity mapping. However, if
the kernel uses more than 2 GB (VMSPLIT_2G_OPT or VMSPLIT_1G memory
split), the normal memory mapping is overwritten by the low identity
mapping causing a crash. To avoid overwritting, limit the low identity
map to cover only memory before kernel range (PAGE_OFFSET).
Fixes: f5f3497cad "x86/setup: Extend low identity map to cover whole kernel range
Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Link: http://lkml.kernel.org/r/1446815916-22105-1-git-send-email-krzysiek@podlesie.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit f5f3497cad upstream.
On 32-bit systems, the initial_page_table is reused by
efi_call_phys_prolog as an identity map to call
SetVirtualAddressMap. efi_call_phys_prolog takes care of
converting the current CPU's GDT to a physical address too.
For PAE kernels the identity mapping is achieved by aliasing the
first PDPE for the kernel memory mapping into the first PDPE
of initial_page_table. This makes the EFI stub's trick "just work".
However, for non-PAE kernels there is no guarantee that the identity
mapping in the initial_page_table extends as far as the GDT; in this
case, accesses to the GDT will cause a page fault (which quickly becomes
a triple fault). Fix this by copying the kernel mappings from
swapper_pg_dir to initial_page_table twice, both at PAGE_OFFSET and at
identity mapping.
For some reason, this is only reproducible with QEMU's dynamic translation
mode, and not for example with KVM. However, even under KVM one can clearly
see that the page table is bogus:
$ qemu-system-i386 -pflash OVMF.fd -M q35 vmlinuz0 -s -S -daemonize
$ gdb
(gdb) target remote localhost:1234
(gdb) hb *0x02858f6f
Hardware assisted breakpoint 1 at 0x2858f6f
(gdb) c
Continuing.
Breakpoint 1, 0x02858f6f in ?? ()
(gdb) monitor info registers
...
GDT= 0724e000 000000ff
IDT= fffbb000 000007ff
CR0=0005003b CR2=ff896000 CR3=032b7000 CR4=00000690
...
The page directory is sane:
(gdb) x/4wx 0x32b7000
0x32b7000: 0x03398063 0x03399063 0x0339a063 0x0339b063
(gdb) x/4wx 0x3398000
0x3398000: 0x00000163 0x00001163 0x00002163 0x00003163
(gdb) x/4wx 0x3399000
0x3399000: 0x00400003 0x00401003 0x00402003 0x00403003
but our particular page directory entry is empty:
(gdb) x/1wx 0x32b7000 + (0x724e000 >> 22) * 4
0x32b7070: 0x00000000
[ It appears that you can skate past this issue if you don't receive
any interrupts while the bogus GDT pointer is loaded, or if you avoid
reloading the segment registers in general.
Andy Lutomirski provides some additional insight:
"AFAICT it's entirely permissible for the GDTR and/or LDT
descriptor to point to unmapped memory. Any attempt to use them
(segment loads, interrupts, IRET, etc) will try to access that memory
as if the access came from CPL 0 and, if the access fails, will
generate a valid page fault with CR2 pointing into the GDT or
LDT."
Up until commit 23a0d4e8fa ("efi: Disable interrupts around EFI
calls, not in the epilog/prolog calls") interrupts were disabled
around the prolog and epilog calls, and the functional GDT was
re-installed before interrupts were re-enabled.
Which explains why no one has hit this issue until now. ]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reported-by: Laszlo Ersek <lersek@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
[ Updated changelog. ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 656ec4a492 upstream.
The comment in code had it mostly right, but we enable paging for
emulated real mode regardless of EPT.
Without EPT (which implies emulated real mode), secondary VCPUs won't
start unless we disable SM[AE]P when the guest doesn't use paging.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit ab45fb1450 upstream.
There are multiple factors adding to the issue in different
configurations:
- commit 17290231df ("xtensa: add fixup for double exception raised
in window overflow") added function window_overflow_restore_a0_fixup to
double exception vector overlapping reset vector location of secondary
processor cores.
- on MMUv2 cores RESET_VECTOR1_VADDR may point to uncached kernel memory
making code overlapping depend on cache type and size, so that without
cache or with WT cache reset vector code overwrites double exception
code, making issue even harder to detect.
- on MMUv3 cores RESET_VECTOR1_VADDR may point to unmapped area, as
MMUv3 cores change virtual address map to match MMUv2 layout, but
reset vector virtual address is given for the original MMUv3 mapping.
- physical memory region of the secondary reset vector is not reserved
in the physical memory map, and thus may be allocated and overwritten
at arbitrary moment.
Fix it as follows:
- move window_overflow_restore_a0_fixup code to .text section.
- define RESET_VECTOR1_VADDR so that it points to reset vector in the
cacheable MMUv2 map for cores with MMU.
- reserve reset vector region in the physical memory map. Drop separate
literal section and build mxhead.S with text section literals.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 5029615e25 upstream.
Build-time fixes:
- make lbeg/lend/lcount save/restore conditional on kernel entry;
- don't clear lcount in platform_restart functions unconditionally.
Run-time fixes:
- use correct end of range register in __endla paired with __loopt, not
the unused temporary register. This fixes .bss zero-initialization.
Update comments in asmmacro.h;
- don't clobber a10 in the usercopy that leads to access to unmapped
memory.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 5accd17d0e upstream.
For reasons not entirely apparent, but now enshrined in history, the
architectural mapping of AArch32 banked registers to AArch64 registers
actually orders SP_<mode> and LR_<mode> backwards compared to the
intuitive r13/r14 order, for all modes except FIQ.
Fix the compat_<reg>_<mode> macros accordingly, in the hope of avoiding
subtle bugs with KVM and AArch32 guests.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit c5c2c39346 upstream.
We seemed to have missed a few corner cases in commit f6c137ff00
("KVM: s390: randomize sca address").
The SCA has a maximum size of 2112 bytes. By setting the sca_offset to
some unlucky numbers, we exceed the page.
0x7c0 (1984) -> Fits exactly
0x7d0 (2000) -> 16 bytes out
0x7e0 (2016) -> 32 bytes out
0x7f0 (2032) -> 48 bytes out
One VCPU entry is 32 bytes long.
For the last two cases, we actually write data to the other page.
1. The address of the VCPU.
2. Injection/delivery/clearing of SIGP externall calls via SIGP IF.
Especially the 2. happens regularly. So this could produce two problems:
1. The guest losing/getting external calls.
2. Random memory overwrites in the host.
So this problem happens on every 127 + 128 created VM with 64 VCPUs.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 696d8b70c0 upstream.
In case when the interrupt happened for the second eDMA the channel
number was incorrectly passed to the client driver.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 7e31210349 upstream.
IOMMU-based dma_mmap() implementation lacked proper support for offset
parameter used in mmap call (it always assumed that mapping starts from
offset zero). This patch adds support for offset parameter to IOMMU-based
implementation.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 371f0f085f upstream.
dma_mmap() function in IOMMU-based dma-mapping implementation lacked
a check for valid range of mmap parameters (offset and buffer size), what
might have caused access beyond the allocated buffer. This patch fixes
this issue.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 64c98e7f49 upstream.
Sanitizing the e820 map may produce extra E820 entries which would result in
the topmost E820 entries being removed. The removed entries would typically
include the top E820 usable RAM region and thus result in the domain having
signicantly less RAM available to it.
Fix by allowing sanitize_e820_map to use the full size of the allocated E820
array.
Signed-off-by: Malcolm Crossley <malcolm.crossley@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
[ luis: backported to 3.16:
- use 'map' instead of 'xen_e820_map_entries' ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit fe32d3cd5e upstream.
These functions check should_resched() before unlocking spinlock/bh-enable:
preempt_count always non-zero => should_resched() always returns false.
cond_resched_lock() worked iff spin_needbreak is set.
This patch adds argument "preempt_offset" to should_resched().
preempt_count offset constants for that:
PREEMPT_DISABLE_OFFSET - offset after preempt_disable()
PREEMPT_LOCK_OFFSET - offset after spin_lock()
SOFTIRQ_DISABLE_OFFSET - offset after local_bh_distable()
SOFTIRQ_LOCK_OFFSET - offset after spin_lock_bh()
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: bdb4380658 ("sched: Extract the basic add/sub preempt_count modifiers")
Link: http://lkml.kernel.org/r/20150715095204.12246.98268.stgit@buzz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[ luis: backported to 3.16:
- some of the changes done in preempt_mask.h instead of preempt.h
- adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 9702970c7b upstream.
This reverts commit e306dfd06f.
With this patch applied, we were the only architecture making this sort
of adjustment to the PC calculation in the unwinder. This causes
problems for ftrace, where the PC values are matched against the
contents of the stack frames in the callchain and fail to match any
records after the address adjustment.
Whilst there has been some effort to change ftrace to workaround this,
those patches are not yet ready for mainline and, since we're the odd
architecture in this regard, let's just step in line with other
architectures (like arch/arm/) for now.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 8832317f66 upstream.
Currently we do not validate rtas.entry before calling enter_rtas(). This
leads to a kernel oops when user space calls rtas system call on a powernv
platform (see below). This patch adds code to validate rtas.entry before
making enter_rtas() call.
Oops: Exception in kernel mode, sig: 4 [#1]
SMP NR_CPUS=1024 NUMA PowerNV
task: c000000004294b80 ti: c0000007e1a78000 task.ti: c0000007e1a78000
NIP: 0000000000000000 LR: 0000000000009c14 CTR: c000000000423140
REGS: c0000007e1a7b920 TRAP: 0e40 Not tainted (3.18.17-340.el7_1.pkvm3_1_0.2400.1.ppc64le)
MSR: 1000000000081000 <HV,ME> CR: 00000000 XER: 00000000
CFAR: c000000000009c0c SOFTE: 0
NIP [0000000000000000] (null)
LR [0000000000009c14] 0x9c14
Call Trace:
[c0000007e1a7bba0] [c00000000041a7f4] avc_has_perm_noaudit+0x54/0x110 (unreliable)
[c0000007e1a7bd80] [c00000000002ddc0] ppc_rtas+0x150/0x2d0
[c0000007e1a7be30] [c000000000009358] syscall_exit+0x0/0x98
Fixes: 55190f8878 ("powerpc: Add skeleton PowerNV platform")
Reported-by: NAGESWARA R. SASTRY <nasastry@in.ibm.com>
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
[mpe: Reword change log, trim oops, and add stable + fixes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 8a53554e12 upstream.
When multiple GOP devices exists, but none of them implements
ConOut, the code should just choose the first GOP (according to
the comments). But currently 'fb_base' will refer to the last GOP,
while other parameters to the first GOP, which will likely
result in a garbled display.
I can reliably reproduce this bug using my ASRock Z87M Extreme4
motherboard with CSM and integrated GPU disabled, and two PCIe
video cards (NVidia GT640 and GTX980), booting from efi-stub
(booting from grub works fine). On the primary display the
ASRock logo remains and on the secondary screen it is garbled
up completely.
Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1444659236-24837-2-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit d836ace65e upstream.
DSA expects the host_dev pointer to be the device structure associated
with the MDIO bus controller driver. First commit breaking that was
c3a07134e6 ("mv643xx_eth: convert to use the Marvell Orion MDIO
driver"), and then, it got completely under the radar for a while.
Reported-by: Frans van de Wiel <fvdw@fvdw.eu>
Fixes: c3a07134e6 ("mv643xx_eth: convert to use the Marvell Orion MDIO driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit b6dd8e0719 upstream.
Commit df057cc7b4 ("arm64: errata: add module build workaround for
erratum #843419") sets CFLAGS_MODULE to ensure that the large memory
model is used by the compiler when building kernel modules.
However, CFLAGS_MODULE is an environment variable and intended to be
overridden on the command line, which appears to be the case with the
Ubuntu kernel packaging system, so use KBUILD_CFLAGS_MODULE instead.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Fixes: df057cc7b4 ("arm64: errata: add module build workaround for erratum #843419")
Reported-by: Dann Frazier <dann.frazier@canonical.com>
Tested-by: Dann Frazier <dann.frazier@canonical.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit a66d7f724a upstream.
Some of the crypto algorithms write to the initialization vector,
but no space has been allocated for it. This clobbers adjacent memory.
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 569ba74a7b upstream.
This is the arm64 portion of commit 45cac65b0f ("readahead: fault
retry breaks mmap file read random detection"), which was absent from
the initial port and has since gone unnoticed. The original commit says:
> .fault now can retry. The retry can break state machine of .fault. In
> filemap_fault, if page is miss, ra->mmap_miss is increased. In the second
> try, since the page is in page cache now, ra->mmap_miss is decreased. And
> these are done in one fault, so we can't detect random mmap file access.
>
> Add a new flag to indicate .fault is tried once. In the second try, skip
> ra->mmap_miss decreasing. The filemap_fault state machine is ok with it.
With this change, Mark reports that:
> Random read improves by 250%, sequential read improves by 40%, and
> random write by 400% to an eMMC device with dm crypto wrapped around it.
Cc: Shaohua Li <shli@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Signed-off-by: Riley Andrews <riandrews@android.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit adc0b7fbf6 upstream.
my gcc 5.1 used an ldgr instruction with a register != 0,2,4,6 for
spilling/filling into a floating point register in our decompressor.
This will cause an AFP-register data exception as the decompressor
did not setup the additional floating point registers via cr0.
That causes a program check loop that looked like a hang with
one "Uncompressing Linux... " message (directly booted via kvm)
or a loop of "Uncompressing Linux... " messages (when booted via
zipl boot loader).
The offending code in my build was
48e400: e3 c0 af ff ff 71 lay %r12,-1(%r10)
-->48e406: b3 c1 00 1c ldgr %f1,%r12
48e40a: ec 6c 01 22 02 7f clij %r6,2,12,0x48e64e
but gcc could do spilling into an fpr at any function. We can
simply disable floating point support at that early stage.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 0b34a166f2 upstream.
Currently there is a number of issues preventing PVHVM Xen guests from
doing successful kexec/kdump:
- Bound event channels.
- Registered vcpu_info.
- PIRQ/emuirq mappings.
- shared_info frame after XENMAPSPACE_shared_info operation.
- Active grant mappings.
Basically, newly booted kernel stumbles upon already set up Xen
interfaces and there is no way to reestablish them. In Xen-4.7 a new
feature called 'soft reset' is coming. A guest performing kexec/kdump
operation is supposed to call SCHEDOP_shutdown hypercall with
SHUTDOWN_soft_reset reason before jumping to new kernel. Hypervisor
(with some help from toolstack) will do full domain cleanup (but
keeping its memory and vCPU contexts intact) returning the guest to
the state it had when it was first booted and thus allowing it to
start over.
Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is
probably OK as by default all unknown shutdown reasons cause domain
destroy with a message in toolstack log: 'Unknown shutdown reason code
5. Destroying domain.' which gives a clue to what the problem is and
eliminates false expectations.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
[ luis: backported to 3.16:
- use CONFIG_KEXEC instead of CONFIG_KEXEC_CORE, as suggested by
David Vrabel ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit ab76f7b4ab upstream.
Unused space between the end of __ex_table and the start of
rodata can be left W+x in the kernel page tables. Extend the
setting of the NX bit to cover this gap by starting from
text_end rather than rodata_start.
Before:
---[ High Kernel Mapping ]---
0xffffffff80000000-0xffffffff81000000 16M pmd
0xffffffff81000000-0xffffffff81600000 6M ro PSE GLB x pmd
0xffffffff81600000-0xffffffff81754000 1360K ro GLB x pte
0xffffffff81754000-0xffffffff81800000 688K RW GLB x pte
0xffffffff81800000-0xffffffff81a00000 2M ro PSE GLB NX pmd
0xffffffff81a00000-0xffffffff81b3b000 1260K ro GLB NX pte
0xffffffff81b3b000-0xffffffff82000000 4884K RW GLB NX pte
0xffffffff82000000-0xffffffff82200000 2M RW PSE GLB NX pmd
0xffffffff82200000-0xffffffffa0000000 478M pmd
After:
---[ High Kernel Mapping ]---
0xffffffff80000000-0xffffffff81000000 16M pmd
0xffffffff81000000-0xffffffff81600000 6M ro PSE GLB x pmd
0xffffffff81600000-0xffffffff81754000 1360K ro GLB x pte
0xffffffff81754000-0xffffffff81800000 688K RW GLB NX pte
0xffffffff81800000-0xffffffff81a00000 2M ro PSE GLB NX pmd
0xffffffff81a00000-0xffffffff81b3b000 1260K ro GLB NX pte
0xffffffff81b3b000-0xffffffff82000000 4884K RW GLB NX pte
0xffffffff82000000-0xffffffff82200000 2M RW PSE GLB NX pmd
0xffffffff82200000-0xffffffffa0000000 478M pmd
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1443704662-3138-1-git-send-email-sds@tycho.nsa.gov
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit d2922422c4 upstream.
The cpu feature flags are not ever going to change, so warning
everytime can cause a lot of kernel log spam
(in our case more than 10GB/hour).
The warning seems to only occur when nested virtualization is
enabled, so it's probably triggered by a KVM bug. This is a
sensible and safe change anyway, and the KVM bug fix might not
be suitable for stable releases anyway.
Signed-off-by: Dirk Mueller <dmueller@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit a5caa209ba upstream.
Beginning with UEFI v2.5 EFI_PROPERTIES_TABLE was introduced
that signals that the firmware PE/COFF loader supports splitting
code and data sections of PE/COFF images into separate EFI
memory map entries. This allows the kernel to map those regions
with strict memory protections, e.g. EFI_MEMORY_RO for code,
EFI_MEMORY_XP for data, etc.
Unfortunately, an unwritten requirement of this new feature is
that the regions need to be mapped with the same offsets
relative to each other as observed in the EFI memory map. If
this is not done crashes like this may occur,
BUG: unable to handle kernel paging request at fffffffefe6086dd
IP: [<fffffffefe6086dd>] 0xfffffffefe6086dd
Call Trace:
[<ffffffff8104c90e>] efi_call+0x7e/0x100
[<ffffffff81602091>] ? virt_efi_set_variable+0x61/0x90
[<ffffffff8104c583>] efi_delete_dummy_variable+0x63/0x70
[<ffffffff81f4e4aa>] efi_enter_virtual_mode+0x383/0x392
[<ffffffff81f37e1b>] start_kernel+0x38a/0x417
[<ffffffff81f37495>] x86_64_start_reservations+0x2a/0x2c
[<ffffffff81f37582>] x86_64_start_kernel+0xeb/0xef
Here 0xfffffffefe6086dd refers to an address the firmware
expects to be mapped but which the OS never claimed was mapped.
The issue is that included in these regions are relative
addresses to other regions which were emitted by the firmware
toolchain before the "splitting" of sections occurred at
runtime.
Needless to say, we don't satisfy this unwritten requirement on
x86_64 and instead map the EFI memory map entries in reverse
order. The above crash is almost certainly triggerable with any
kernel newer than v3.13 because that's when we rewrote the EFI
runtime region mapping code, in commit d2f7cbe7b2 ("x86/efi:
Runtime services virtual mapping"). For kernel versions before
v3.13 things may work by pure luck depending on the
fragmentation of the kernel virtual address space at the time we
map the EFI regions.
Instead of mapping the EFI memory map entries in reverse order,
where entry N has a higher virtual address than entry N+1, map
them in the same order as they appear in the EFI memory map to
preserve this relative offset between regions.
This patch has been kept as small as possible with the intention
that it should be applied aggressively to stable and
distribution kernels. It is very much a bugfix rather than
support for a new feature, since when EFI_PROPERTIES_TABLE is
enabled we must map things as outlined above to even boot - we
have no way of asking the firmware not to split the code/data
regions.
In fact, this patch doesn't even make use of the more strict
memory protections available in UEFI v2.5. That will come later.
Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chun-Yi <jlee@suse.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: James Bottomley <JBottomley@Odin.com>
Cc: Lee, Chun-Yi <jlee@suse.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1443218539-7610-2-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 7a63076d9a upstream.
The CONFIG_MIPS_MT symbol can be selected by CONFIG_MIPS_VPE_LOADER in
addition to CONFIG_MIPS_MT_SMP. We only want MT code in the CPS SMP boot
vector if we're using MT for SMP. Thus switch the config symbol we ifdef
against to CONFIG_MIPS_MT_SMP.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10867/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit a5b0f6db0e upstream.
The MT-specific code in mips_cps_boot_vpes can safely be omitted from
kernels which don't support MT, with the default VPE==0 case being used
as it would be after the has_mt (Config3.MT) check failed at runtime.
Discarding the code entirely will save us a few bytes & allow cleaner
handling of MT ASE instructions by later patches.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10866/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 1e5fb282f8 upstream.
The has_mt macro ended with a branch, leaving its callers with a delay
slot that would be executed if Config3.MT is not set. However it would
not be executed if Config3 (or earlier Config registers) don't exist
which makes it somewhat inconsistent at best. Fill the delay slot in the
macro & fix the mips_cps_boot_vpes caller appropriately.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10865/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 53960059d5 upstream.
If there is a DMA zone (usually 24bit = 16MB I believe), but no DMA32
zone, as is the case for some 32-bit kernels, then massage_gfp_flags()
will cause DMA memory allocated for devices with a 32..63-bit
coherent_dma_mask to fall back to using __GFP_DMA, even though there may
only be 32-bits of physical address available anyway.
Correct that case to compare against a mask the size of phys_addr_t
instead of always using a 64-bit mask.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Fixes: a2e715a86c ("MIPS: DMA: Fix computation of DMA flags from device's coherent_dma_mask.")
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9610/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 8474ba7419 upstream.
Make sure the compiler does not modify arguments of syscall functions.
This can happen if the compiler generates a tailcall to another
function. For example, without asmlinkage_protect sys_openat is compiled
into this function:
sys_openat:
clr.l %d0
move.w 18(%sp),%d0
move.l %d0,16(%sp)
jbra do_sys_open
Note how the fourth argument is modified in place, modifying the register
%d4 that gets restored from this stack slot when the function returns to
user-space. The caller may expect the register to be unmodified across
system calls.
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
This reverts commit b5614b199b,
which was commit 5be9fc23cd upstream.
Ben Hutchings pointed out this was not applicable to the 3.16-ckt kernel.
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Benjamin Cama <benoar@dolka.fr>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 1dbdad7507 upstream.
The i2c5 pinctrl offsets are wrong. If the bootloader doesn't set the
pins up, communication with tca6424a doesn't work (controller timeouts)
and it is not possible to enable HDMI.
Fixes: 9be495c426 ("ARM: dts: omap5-evm: Add I2c pinctrl data")
Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 83c133cf11 upstream.
The NMI entry code that switches to the normal kernel stack needs to
be very careful not to clobber any extra stack slots on the NMI
stack. The code is fine under the assumption that SWAPGS is just a
normal instruction, but that assumption isn't really true. Use
SWAPGS_UNSAFE_STACK instead.
This is part of a fix for some random crashes that Sasha saw.
Fixes: 9b6e6a8334 ("x86/nmi/64: Switch stacks on userspace NMI entry")
Reported-and-tested-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Link: http://lkml.kernel.org/r/974bc40edffdb5c2950a5c4977f821a446b76178.1442791737.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ luis: backported to 3.16:
- file rename: arch/x86/entry/entry_64.S -> arch/x86/kernel/entry_64.S
- adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit fc57a7c680 upstream.
PARAVIRT_ADJUST_EXCEPTION_FRAME generates this code (using nmi as an
example, trimmed for readability):
ff 15 00 00 00 00 callq *0x0(%rip) # 2796 <nmi+0x6>
2792: R_X86_64_PC32 pv_irq_ops+0x2c
That's a call through a function pointer to regular C function that
does nothing on native boots, but that function isn't protected
against kprobes, isn't marked notrace, and is certainly not
guaranteed to preserve any registers if the compiler is feeling
perverse. This is bad news for a CLBR_NONE operation.
Of course, if everything works correctly, once paravirt ops are
patched, it gets nopped out, but what if we hit this code before
paravirt ops are patched in? This can potentially cause breakage
that is very difficult to debug.
A more subtle failure is possible here, too: if _paravirt_nop uses
the stack at all (even just to push RBP), it will overwrite the "NMI
executing" variable if it's called in the NMI prologue.
The Xen case, perhaps surprisingly, is fine, because it's already
written in asm.
Fix all of the cases that default to paravirt_nop (including
adjust_exception_frame) with a big hammer: replace paravirt_nop with
an asm function that is just a ret instruction.
The Xen case may have other problems, so document them.
This is part of a fix for some random crashes that Sasha saw.
Reported-and-tested-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Link: http://lkml.kernel.org/r/8f5d2ba295f9d73751c33d97fda03e0495d9ade0.1442791737.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ luis: backported to 3.16:
- file rename: arch/x86/entry/entry_64.S -> arch/x86/kernel/entry_64.S
- adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 3afb112180 upstream.
These have roughly the same purpose as the SMRR, which we do not need
to implement in KVM. However, Linux accesses MSR_K8_TSEG_ADDR at
boot, which causes problems when running a Xen dom0 under KVM.
Just return 0, meaning that processor protection of SMRAM is not
in effect.
Reported-by: M A Young <m.a.young@durham.ac.uk>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[ luis: backported to 3.16:
- file rename: arch/x86/include/asm/msr-index.h ->
arch/x86/include/uapi/asm/msr-index.h
- adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 3a2fa775bd upstream.
Let's fix pinmux address of gpio 170 used by tfp410 powerdown-gpio.
According to the OMAP35x Technical Reference Manual
CONTROL_PADCONF_I2C3_SDA[15:0] 0x480021C4 mode0: i2c3_sda
CONTROL_PADCONF_I2C3_SDA[31:16] 0x480021C4 mode4: gpio_170
the pinmux address of gpio 170 must be 0x480021C6.
The former wrong address broke i2c3 (used by hdmi ddc), resulting in
kernel message:
omap_i2c 48060000.i2c: controller timed out
Fixes: 8cecf52bef ("ARM: omap3-beagle.dts: add display information")
Signed-off-by: Carl Frederik Werner <frederik@cfbw.eu>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 688bc577ac upstream.
When running a guest with the architected timer disabled (with QEMU and
the kernel_irqchip=off option, for example), it is important to make
sure the timer gets turned off. Otherwise, the guest may try to
enable it anyway, leading to a screaming HW interrupt.
The fix is to unconditionally turn off the virtual timer on guest
exit.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit c4cbba9fa0 upstream.
When running a guest with the architected timer disabled (with QEMU and
the kernel_irqchip=off option, for example), it is important to make
sure the timer gets turned off. Otherwise, the guest may try to
enable it anyway, leading to a screaming HW interrupt.
The fix is to unconditionally turn off the virtual timer on guest
exit.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit df057cc7b4 upstream.
Cortex-A53 processors <= r0p4 are affected by erratum #843419 which can
lead to a memory access using an incorrect address in certain sequences
headed by an ADRP instruction.
There is a linker fix to generate veneers for ADRP instructions, but
this doesn't work for kernel modules which are built as unlinked ELF
objects.
This patch adds a new config option for the erratum which, when enabled,
builds kernel modules with the mcmodel=large flag. This uses absolute
addressing for all kernel symbols, thereby removing the use of ADRP as
a PC-relative form of addressing. The ADRP relocs are removed from the
module loader so that we fail to load any potentially affected modules.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit bdec97a855 upstream.
When saving/restoring the VFP registers from a compat (AArch32)
signal frame, we rely on the compat registers forming a prefix of the
native register file and therefore make use of copy_{to,from}_user to
transfer between the native fpsimd_state and the compat_vfp_sigframe.
Unfortunately, this doesn't work so well in a big-endian environment.
Our fpsimd save/restore code operates directly on 128-bit quantities
(Q registers) whereas the compat_vfp_sigframe represents the registers
as an array of 64-bit (D) registers. The architecture packs the compat D
registers into the Q registers, with the least significant bytes holding
the lower register. Consequently, we need to swap the 64-bit halves when
converting between these two representations on a big-endian machine.
This patch replaces the __copy_{to,from}_user invocations in our
compat VFP signal handling code with explicit __put_user loops that
operate on 64-bit values and swap them accordingly.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
