commit 8dbc1864b7 upstream.
Commit 17278a91e0 ("MIPS: CPS: Fix r1 .set mt assembler warning")
added .set MIPS_ISA_LEVEL_RAW to silence warnings about .set mt on r1,
however this can result in a MOVE being encoded as a 64-bit DADDU
instruction on certain version of binutils (e.g. 2.22), and reserved
instruction exceptions at runtime on 32-bit hardware.
Reduce the sizes of the push/pop sections to include only instructions
that are part of the MT ASE or which won't convert to 64-bit
instructions after .set mips64r2/mips64r6.
Reported-by: Greg Ungerer <gerg@linux-m68k.org>
Fixes: 17278a91e0 ("MIPS: CPS: Fix r1 .set mt assembler warning")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Tested-by: Greg Ungerer <gerg@linux-m68k.org>
Patchwork: https://patchwork.linux-mips.org/patch/18578/
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 7e702d17ed upstream.
Commit b94b737331 ("x86/microcode/intel: Extend BDW late-loading with a
revision check") reduced the impact of erratum BDF90 for Broadwell model
79.
The impact can be reduced further by checking the size of the last level
cache portion per core.
Tony: "The erratum says the problem only occurs on the large-cache SKUs.
So we only need to avoid the update if we are on a big cache SKU that is
also running old microcode."
For more details, see erratum BDF90 in document #334165 (Intel Xeon
Processor E7-8800/4800 v4 Product Family Specification Update) from
September 2017.
Fixes: b94b737331 ("x86/microcode/intel: Extend BDW late-loading with a revision check")
Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/1516321542-31161-1-git-send-email-zhang.jia@linux.alibaba.com
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 6f41c34d69 upstream.
The machine check idtentry uses an indirect branch directly from the low
level code. This evades the speculation protection.
Replace it by a direct call into C code and issue the indirect call there
so the compiler can apply the proper speculation protection.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by:Borislav Petkov <bp@alien8.de>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Niced-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801181626290.1847@nanos
[bwh: Backported to 3.16
- #include <asm/traps.h> in mce.c
- Adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 37b95951c5 upstream.
kvm_valid_sregs() should use X86_CR0_PG and X86_CR4_PAE to check bit
status rather than X86_CR0_PG_BIT and X86_CR4_PAE_BIT. This patch is
to fix it.
Fixes: f29810335965a(KVM/x86: Check input paging mode when cs.l is set)
Reported-by: Jeremi Piotrowski <jeremi.piotrowski@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit acfb3b883f upstream.
KVM doesn't follow the SMCCC when it comes to unimplemented calls,
and inject an UNDEF instead of returning an error. Since firmware
calls are now used for security mitigation, they are becoming more
common, and the undef is counter productive.
Instead, let's follow the SMCCC which states that -1 must be returned
to the caller when getting an unknown function number.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
[bwh: Backported to 3.16: use vcpu_reg()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 75f139aaf8 upstream.
This adds a memory barrier when performing a lookup into
the vmcs_field_to_offset_table. This is related to
CVE-2017-5753.
Signed-off-by: Andrew Honig <ahonig@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 349524bc0d upstream.
This causes warnings from cpufreq mutex code. This is also rather
unnecessary and ineffective. If we really want to prevent concurrent
unplug, we could take the unplug read lock but I don't see this being
critical.
Fixes: cd77b5ce20 ("powerpc/powernv/cpufreq: Fix the frequency read by /proc/cpuinfo")
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit f9a531d673 upstream.
After the Ether platform data is fixed, the driver probe() method would
still fail since the 'struct sh_eth_cpu_data' corresponding to SH771x
indicates the presence of TSU but the memory resource for it is absent.
Add the missing TSU resource to both Ether devices and fix the harmless
off-by-one error in the main memory resources, while at it...
Fixes: 4986b99688 ("net: sh_eth: remove the SH_TSU_ADDR")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 195e2addbc upstream.
The 'sh_eth' driver's probe() method would fail on the SolutionEngine7710
board and crash on SolutionEngine7712 board as the platform code is
hopelessly behind the driver's platform data -- it passes the PHY address
instead of 'struct sh_eth_plat_data *'; pass the latter to the driver in
order to fix the bug...
Fixes: 71557a37ad ("[netdrvr] sh_eth: Add SH7619 support")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit b94b737331 upstream.
Instead of blacklisting all model 79 CPUs when attempting a late
microcode loading, limit that only to CPUs with microcode revisions <
0x0b000021 because only on those late loading may cause a system hang.
For such processors either:
a) a BIOS update which might contain a newer microcode revision
or
b) the early microcode loading method
should be considered.
Processors with revisions 0x0b000021 or higher will not experience such
hangs.
For more details, see erratum BDF90 in document #334165 (Intel Xeon
Processor E7-8800/4800 v4 Product Family Specification Update) from
September 2017.
[ bp: Heavily massage commit message and pr_* statements. ]
Fixes: 723f2828a9 ("x86/microcode/intel: Disable late loading on model 79")
Signed-off-by: Jia Zhang <qianyue.zj@alibaba-inc.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/1514772287-92959-1-git-send-email-qianyue.zj@alibaba-inc.com
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
' at end of ALTERNATIVE inline asm
commit b9e705ef7c upstream.
Where an ALTERNATIVE is used in the middle of an inline asm block, this
would otherwise lead to the following instruction being appended directly
to the trailing ".popsection", and a failed compile.
Fixes: 9cebed423c ("x86, alternative: Use .pushsection/.popsection")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: ak@linux.intel.com
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Turner <pjt@google.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Link: https://lkml.kernel.org/r/20180104143710.8961-8-dwmw@amazon.co.uk
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 56aeb07c91 upstream.
MPP7 is currently muxed as "gpio", but this function doesn't exist for
MPP7, only "gpo" is available. This causes the following error:
kirkwood-pinctrl f1010000.pin-controller: unsupported function gpio on pin mpp7
pinctrl core: failed to register map default (6): invalid type given
kirkwood-pinctrl f1010000.pin-controller: error claiming hogs: -22
kirkwood-pinctrl f1010000.pin-controller: could not claim hogs: -22
kirkwood-pinctrl f1010000.pin-controller: unable to register pinctrl driver
kirkwood-pinctrl: probe of f1010000.pin-controller failed with error -22
So the pinctrl driver is not probed, all device drivers (including the
UART driver) do a -EPROBE_DEFER, and therefore the system doesn't
really boot (well, it boots, but with no UART, and no devices that
require pin-muxing).
Back when the Device Tree file for this board was introduced, the
definition was already wrong. The pinctrl driver also always described
as "gpo" this function for MPP7. However, between Linux 4.10 and 4.11,
a hog pin failing to be muxed was turned from a simple warning to a
hard error that caused the entire pinctrl driver probe to bail
out. This is probably the result of commit 6118714275 ("pinctrl:
core: Fix pinctrl_register_and_init() with pinctrl_enable()").
This commit fixes the Device Tree to use the proper "gpo" function for
MPP7, which fixes the boot of OpenBlocks A7, which was broken since
Linux 4.11.
Fixes: f24b56cbcd ("ARM: kirkwood: add support for OpenBlocks A7 platform")
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 7839c672e5 upstream.
When we unmap the HYP memory, we try to be clever and unmap one
PGD at a time. If we start with a non-PGD aligned address and try
to unmap a whole PGD, things go horribly wrong in unmap_hyp_range
(addr and end can never match, and it all goes really badly as we
keep incrementing pgd and parse random memory as page tables...).
The obvious fix is to let unmap_hyp_range do what it does best,
which is to iterate over a range.
The size of the linear mapping, which begins at PAGE_OFFSET, can be
easily calculated by subtracting PAGE_OFFSET form high_memory, because
high_memory is defined as the linear map address of the last byte of
DRAM, plus one.
The size of the vmalloc region is given trivially by VMALLOC_END -
VMALLOC_START.
Reported-by: Andre Przywara <andre.przywara@arm.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
[bwh: Backported to 3.16: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit bdcf0a423e upstream.
In testing, we found that nfsd threads may call set_groups in parallel
for the same entry cached in auth.unix.gid, racing in the call of
groups_sort, corrupting the groups for that entry and leading to
permission denials for the client.
This patch:
- Make groups_sort globally visible.
- Move the call to groups_sort to the modifiers of group_info
- Remove the call to groups_sort from set_groups
Link: http://lkml.kernel.org/r/20171211151420.18655-1-thiago.becker@gmail.com
Signed-off-by: Thiago Rafael Becker <thiago.becker@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Acked-by: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit f41d84dddc upstream.
It's theoretically possible that branch instructions recorded in
BHRB (Branch History Rolling Buffer) entries have already been
unmapped before they are processed by the kernel. Hence, trying to
dereference such memory location will result in a crash. eg:
Unable to handle kernel paging request for data at address 0xd000000019c41764
Faulting instruction address: 0xc000000000084a14
NIP [c000000000084a14] branch_target+0x4/0x70
LR [c0000000000eb828] record_and_restart+0x568/0x5c0
Call Trace:
[c0000000000eb3b4] record_and_restart+0xf4/0x5c0 (unreliable)
[c0000000000ec378] perf_event_interrupt+0x298/0x460
[c000000000027964] performance_monitor_exception+0x54/0x70
[c000000000009ba4] performance_monitor_common+0x114/0x120
Fix it by deferefencing the addresses safely.
Fixes: 691231846c ("powerpc/perf: Fix setting of "to" addresses for BHRB")
Suggested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
[mpe: Use probe_kernel_read() which is clearer, tweak change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit c8c5a3a24d upstream.
Complement commit c23b3d1a53 ("MIPS: ptrace: Change GP regset to use
correct core dump register layout") and also reject outsized
PTRACE_SETREGSET requests to the NT_PRFPREG regset, like with the
NT_PRSTATUS regset.
Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Fixes: c23b3d1a53 ("MIPS: ptrace: Change GP regset to use correct core dump register layout")
Cc: James Hogan <james.hogan@mips.com>
Cc: Paul Burton <Paul.Burton@mips.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17930/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit be07a6a118 upstream.
Fix a commit 72b22bbad1 ("MIPS: Don't assume 64-bit FP registers for
FP regset") public API regression, then activated by commit 1db1af84d6
("MIPS: Basic MSA context switching support"), that caused the FCSR
register not to be read or written for CONFIG_CPU_HAS_MSA kernel
configurations (regardless of actual presence or absence of the MSA
feature in a given processor) with ptrace(2) PTRACE_GETREGSET and
PTRACE_SETREGSET requests nor recorded in core dumps.
This is because with !CONFIG_CPU_HAS_MSA configurations the whole of
`elf_fpregset_t' array is bulk-copied as it is, which includes the FCSR
in one half of the last, 33rd slot, whereas with CONFIG_CPU_HAS_MSA
configurations array elements are copied individually, and then only the
leading 32 FGR slots while the remaining slot is ignored.
Correct the code then such that only FGR slots are copied in the
respective !MSA and MSA helpers an then the FCSR slot is handled
separately in common code. Use `ptrace_setfcr31' to update the FCSR
too, so that the read-only mask is respected.
Retrieving a correct value of FCSR is important in debugging not only
for the human to be able to get the right interpretation of the
situation, but for correct operation of GDB as well. This is because
the condition code bits in FSCR are used by GDB to determine the
location to place a breakpoint at when single-stepping through an FPU
branch instruction. If such a breakpoint is placed incorrectly (i.e.
with the condition reversed), then it will be missed, likely causing the
debuggee to run away from the control of GDB and consequently breaking
the process of investigation.
Fortunately GDB continues using the older PTRACE_GETFPREGS ptrace(2)
request which is unaffected, so the regression only really hits with
post-mortem debug sessions using a core dump file, in which case
execution, and consequently single-stepping through branches is not
possible. Of course core files created by buggy kernels out there will
have the value of FCSR recorded clobbered, but such core files cannot be
corrected and the person using them simply will have to be aware that
the value of FCSR retrieved is not reliable.
Which also means we can likely get away without defining a replacement
API which would ensure a correct value of FSCR to be retrieved, or none
at all.
This is based on previous work by Alex Smith, extensively rewritten.
Signed-off-by: Alex Smith <alex@alex-smith.me.uk>
Signed-off-by: James Hogan <james.hogan@mips.com>
Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Fixes: 72b22bbad1 ("MIPS: Don't assume 64-bit FP registers for FP regset")
Cc: Paul Burton <Paul.Burton@mips.com>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17928/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit dc24d0edf3 upstream.
Complement commit d614fd58a2 ("mips/ptrace: Preserve previous
registers for short regset write") and ensure that no partial register
write attempt is made with PTRACE_SETREGSET, as we do not preinitialize
any temporaries used to hold incoming register data and consequently
random data could be written.
It is the responsibility of the caller, such as `ptrace_regset', to
arrange for writes to span whole registers only, so here we only assert
that it has indeed happened.
Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Fixes: 72b22bbad1 ("MIPS: Don't assume 64-bit FP registers for FP regset")
Cc: James Hogan <james.hogan@mips.com>
Cc: Paul Burton <Paul.Burton@mips.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17926/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit a03fe72572 upstream.
In preparation to fix a commit 72b22bbad1 ("MIPS: Don't assume 64-bit
FP registers for FP regset") FCSR access regression factor out
NT_PRFPREG regset access helpers for the non-MSA and the MSA variants
respectively, to avoid having to deal with excessive indentation in the
actual fix.
No functional change, however use `target->thread.fpu.fpr[0]' rather
than `target->thread.fpu.fpr[i]' for FGR holding type size determination
as there's no `i' variable to refer to anymore, and for the factored out
`i' variable declaration use `unsigned int' rather than `unsigned' as
its type, following the common style.
Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Fixes: 72b22bbad1 ("MIPS: Don't assume 64-bit FP registers for FP regset")
Cc: James Hogan <james.hogan@mips.com>
Cc: Paul Burton <Paul.Burton@mips.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17925/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit d614fd58a2 upstream.
Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET
to fill all the registers, the thread's old registers are preserved.
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 5a1aca4469 upstream.
Sanitize FCSR Cause bit handling, following a trail of past attempts:
* commit 4249548454 ("MIPS: ptrace: Fix FP context restoration FCSR
regression"),
* commit 443c44032a ("MIPS: Always clear FCSR cause bits after
emulation"),
* commit 64bedffe49 ("MIPS: Clear [MSA]FPE CSR.Cause after
notify_die()"),
* commit b1442d39fa ("MIPS: Prevent user from setting FCSR cause
bits"),
* commit b54d2901517d ("Properly handle branch delay slots in connection
with signals.").
Specifically do not mask these bits out in ptrace(2) processing and send
a SIGFPE signal instead whenever a matching pair of an FCSR Cause and
Enable bit is seen as execution of an affected context is about to
resume. Only then clear Cause bits, and even then do not clear any bits
that are set but masked with the respective Enable bits. Adjust Cause
bit clearing throughout code likewise, except within the FPU emulator
proper where they are set according to IEEE 754 exceptions raised as the
operation emulated executed. Do so so that any IEEE 754 exceptions
subject to their default handling are recorded like with operations
executed by FPU hardware.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Paul Burton <paul.burton@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/14460/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[bwh: Backported to 3.16:
- Drop changes in mips-r2-to-r6-emul and simulate_fp()
- Add #include <asm/fpu.h> in <asm/switch_to.h>
- Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 9cc719ab3f upstream.
Due to the slightly odd way that new threads and processes start execution
when scheduled for the very first time they were bypassing the required
disable_msa call.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit abf378be49 upstream.
Correct the cases missed with commit 9b26616c8d ("MIPS: Respect the
ISA level in FCSR handling") and prevent writes to read-only FCSR bits
there.
This in particular applies to FP context initialisation where any IEEE
754-2008 bits preset by `mips_set_personality_nan' are cleared before
the relevant ptrace(2) call takes effect and the PTRACE_POKEUSR request
addressing FPC_CSR where no masking of read-only FCSR bits is done.
Remove the FCSR clearing from FP context initialisation then and unify
PTRACE_POKEUSR/FPC_CSR and PTRACE_SETFPREGS handling, by factoring out
code from `ptrace_setfpregs' and calling it from both places.
This mostly matters to soft float configurations where the emulator can
be switched this way to a mode which should not be accessible and cannot
be set with the CTC1 instruction. With hard float configurations any
effect is transient anyway as read-only bits will retain their values at
the time the FP context is restored.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13239/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[bwh: Backported to 3.16: There is no mips_set_personality_nan(), so make
init_fp_ctx() copy the initial value of FCSR31]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 4249548454 upstream.
Fix a floating-point context restoration regression introduced with
commit 9b26616c8d ("MIPS: Respect the ISA level in FCSR handling")
that causes a Floating Point exception and consequently a kernel oops
with hard float configurations when one or more FCSR Enable and their
corresponding Cause bits are set both at a time via a ptrace(2) call.
To do so reinstate Cause bit masking originally introduced with commit
b1442d39fa ("MIPS: Prevent user from setting FCSR cause bits") to
address this exact problem and then inadvertently removed from the
PTRACE_SETFPREGS request with the commit referred above.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13238/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 03dce59527 upstream.
Fix "BUG: using smp_processor_id() in preemptible" reported in accesses
to thread's FPU defaults: the value to initialise FSCR to at program
startup, the FCSR r/w mask and the contents of FIR in full FPU
emulation, removing a regression introduced with 9b26616c [MIPS: Respect
the ISA level in FCSR handling] and f6843626 [MIPS: math-emu: Set FIR
feature flags for full emulation].
Use `boot_cpu_data' to obtain the data from, following the approach that
`cpu_has_*' macros take and avoiding the call to `smp_processor_id' made
in the reference to `current_cpu_data'. The contents of FSCR have to be
consistent across processors in an SMP system, the settings there must
not change as a thread is migrated across processors. And the contents
of FIR are guaranteed to be consistent in FPU emulation, by definition.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Tested-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Tested-by: Paul Martin <paul.martin@codethink.co.uk>
Cc: Markos Chandras <Markos.Chandras@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10030/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[bwh: Backported to 3.16:
- Drop change in cop1_cfc()
- Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 9b26616c8d upstream.
Define the central place the default FCSR value is set from, initialised
in `cpu_probe'. Determine the FCSR mask applied to values written to
the register with CTC1 in the full emulation mode and via ptrace(2),
according to the ISA level of processor hardware or the writability of
bits 31:18 if actual FPU hardware is used.
Software may rely on FCSR bits whose functions our emulator does not
implement, so it should not allow them to be set or software may get
confused. For ptrace(2) it's just sanity.
[ralf@linux-mips.org: Fixed double inclusion of <asm/current.h>.]
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9711/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[bwh: Backported to 3.16:
- In cop1Emulate(), keep converting the rounding mode
- Drop change in loongson_cu2_call()
- Add definitions of FPU_CSR_{FS,CONDX} in <asm/mipsregs.h>
- Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit f1f3b7ebac upstream.
Define IEEE 754-2008 feature control bits: FIR.HAS2008, FCSR.ABS2008 and
FCSR.NAN2008, and update the `_ieee754_csr' structure accordingly.
For completeness define FIR.UFRP too.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9709/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[bwh: Backported to 3.16: In cop1Emulate(), keep converting the rounding mode]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 304acb717e upstream.
Rework `process_fpemu_return' and move IEEE 754 exception interpretation
there, from `do_fpe'. Record the cause bits set in FCSR before they are
cleared and pass them through to `process_fpemu_return' so as to set
`si_code' correctly too for SIGFPE signals sent from emulation rather
than those issued by hardware with the FPE processor exception only.
For simplicity `mipsr2_decoder' assumes `*fcr31' has been preinitialised
and only sets it to anything if an FPU instruction has been emulated,
which in turn is the only case SIGFPE can be issued for here.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9705/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[bwh: Backported to 3.16:
- Drop changes in mips-r2-to-r6-emul and simulate_fp()
- Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 443c44032a upstream.
Clear any FCSR cause bits recorded in the saved FPU context after
emulation in all cases rather than in `do_fpe' only, so that any
unmasked IEEE 754 exception left from emulation does not cause a fatal
kernel-mode FPE hardware exception with the CTC1 instruction used by the
kernel to subsequently restore FCSR hardware from the saved FPU context.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9704/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[bwh: Backported to 3.16: drop changes in mips-r2-to-r6-emul and simulate_fp()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit ed2d72c1eb upstream.
Respect the FCSR exception mask when interpreting the IEEE 754 exception
condition to report with SIGFPE in `si_code', so as not to use one that
has been masked where a different one set in parallel caused the FPE
hardware exception to trigger. As per the IEEE Std 754 the Inexact
exception can happen together with Overflow or Underflow.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9703/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit acaf6a97d6 upstream.
The lose_fpu() function only disables the FPU in CP0_Status.CU1 if the
FPU is in use and MSA isn't enabled.
This isn't necessarily a problem because KSTK_STATUS(current), the
version of CP0_Status stored on the kernel stack on entry from user
mode, does always get updated and gets restored when returning to user
mode, but I don't think it was intended, and it is inconsistent with the
case of only the FPU being in use. Sometimes leaving the FPU enabled may
also mask kernel bugs where FPU operations are executed when the FPU
might not be enabled.
So lets disable the FPU in the MSA case too.
Fixes: 33c771ba5c ("MIPS: save/disable MSA in lose_fpu")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9323/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit ac9ad83bc3 upstream.
If a ptracee has not used the FPU and the ptracer sets its FP context
using PTRACE_POKEUSR, PTRACE_SETFPREGS or PTRACE_SETREGSET then that
context will be discarded upon either the ptracee using the FPU or a
further write to the context via ptrace. Prevent this loss by recording
that the task has "used" math once its FP context has been written to.
The context initialisation code that was present for the PTRACE_POKEUSR
case is reused for the other 2 cases to provide consistent behaviour
for the different ptrace requests.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9166/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 64bedffe49 upstream.
When handling floating point exceptions (FPEs) and MSA FPEs the Cause
bits of the appropriate control and status register (FCSR for FPEs and
MSACSR for MSA FPEs) are read and cleared before enabling interrupts,
presumably so that it doesn't have to go through the pain of restoring
those bits if the process is pre-empted, since writing those bits would
cause another immediate exception while still in the kernel.
The bits aren't normally ever restored again, since userland never
expects to see them set.
However for virtualisation it is necessary for the kernel to be able to
restore these Cause bits, as the guest may have been interrupted in an
FP exception handler but before it could read the Cause bits. This can
be done by registering a die notifier, to get notified of the exception
when such a value is restored, and if the PC was at the instruction
which is used to restore the guest state, the handler can step over it
and continue execution. The Cause bits can then remain set without
causing further exceptions.
For this to work safely a few changes are made:
- __build_clear_fpe and __build_clear_msa_fpe no longer clear the Cause
bits, and now return from exception level with interrupts disabled
instead of enabled.
- do_fpe() now clears the Cause bits and enables interrupts after
notify_die() is called, so that the notifier can chose to return from
exception without this happening.
- do_msa_fpe() acts similarly, but now actually makes use of the second
argument (msacsr) and calls notify_die() with the new DIE_MSAFP,
allowing die notifiers to be informed of MSA FPEs too.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 091be550a7 upstream.
Much like for traditional scalar FP exceptions, the cause bits in the
MSACSR register need to be cleared following an MSA FP exception.
Without doing so the exception will simply be raised again whenever
the kernel restores MSACSR from a tasks saved context, leading to
undesirable spurious exceptions. Clear the cause bits from the
handle_msa_fpe function, mirroring the way handle_fpe clears the
cause bits in FCSR.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9164/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 17278a91e0 upstream.
MIPS CPS has a build warning on kernels configured for MIPS32R1 or
MIPS64R1, due to the use of .set mt without a prior .set mips{32,64}r2:
arch/mips/kernel/cps-vec.S Assembler messages:
arch/mips/kernel/cps-vec.S:238: Warning: the `mt' extension requires MIPS32 revision 2 or greater
Add .set MIPS_ISA_LEVEL_RAW before .set mt to silence the warning.
Fixes: 245a7868d2 ("MIPS: smp-cps: rework core/VPE initialisation")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <james.hogan@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17699/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 071b6d4a5d upstream.
Currently, loading of a task's fpsimd state into the CPU registers
is skipped if that task's state is already present in the registers
of that CPU.
However, the code relies on the struct fpsimd_state * (and by
extension struct task_struct *) to unambiguously identify a task.
There is a particular case in which this doesn't work reliably:
when a task exits, its task_struct may be recycled to describe a
new task.
Consider the following scenario:
1) Task P loads its fpsimd state onto cpu C.
per_cpu(fpsimd_last_state, C) := P;
P->thread.fpsimd_state.cpu := C;
2) Task X is scheduled onto C and loads its fpsimd state on C.
per_cpu(fpsimd_last_state, C) := X;
X->thread.fpsimd_state.cpu := C;
3) X exits, causing X's task_struct to be freed.
4) P forks a new child T, which obtains X's recycled task_struct.
T == X.
T->thread.fpsimd_state.cpu == C (inherited from P).
5) T is scheduled on C.
T's fpsimd state is not loaded, because
per_cpu(fpsimd_last_state, C) == T (== X) &&
T->thread.fpsimd_state.cpu == C.
(This is the check performed by fpsimd_thread_switch().)
So, T gets X's registers because the last registers loaded onto C
were those of X, in (2).
This patch fixes the problem by ensuring that the sched-in check
fails in (5): fpsimd_flush_task_state(T) is called when T is
forked, so that T->thread.fpsimd_state.cpu == C cannot be true.
This relies on the fact that T is not schedulable until after
copy_thread() completes.
Once T's fpsimd state has been loaded on some CPU C there may still
be other cpus D for which per_cpu(fpsimd_last_state, D) ==
&X->thread.fpsimd_state. But D is necessarily != C in this case,
and the check in (5) must fail.
An alternative fix would be to do refcounting on task_struct. This
would result in each CPU holding a reference to the last task whose
fpsimd state was loaded there. It's not clear whether this is
preferable, and it involves higher overhead than the fix proposed
in this patch. It would also move all the task_struct freeing
work into the context switch critical section, or otherwise some
deferred cleanup mechanism would need to be introduced, neither of
which seems obviously justified.
Fixes: 005f78cd88 ("arm64: defer reloading a task's FPSIMD state to userland resume")
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[will: word-smithed the comment so it makes more sense]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit ddec3bdee0 upstream.
acpi_os_get_root_pointer() may return a valid address even if acpi_disabled
is set, but the host bridge information from the ACPI tables is not going
to be used in that case and the Broadcom host bridge initialization should
not be skipped then, So make broadcom_postcore_init() check acpi_disabled
too to avoid this issue.
Fixes: 6361d72b04 (x86/PCI: read Broadcom CNB20LE host bridge info before PCI scan)
Reported-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Linux PCI <linux-pci@vger.kernel.org>
Link: https://lkml.kernel.org/r/3186627.pxZj1QbYNg@aspire.rjw.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit fbbd7f1a51 upstream.
The switch_to() macro has an optimization to avoid saving and
restoring register contents that aren't needed for kernel threads.
There is however the possibility that a kernel thread execve's a user
space program. In such a case the execve'd process can partially see
the contents of the previous process, which shouldn't be allowed.
To avoid this, simply always save and restore register contents on
context switch.
Fixes: fdb6d070ef ("switch_to: dont restore/save access & fpu regs for kernel threads")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[bwh: Backported to 3.16:
- The save/restore functions are different here
- FP restore is non-lazy, so drop the comment about it being lazy]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 5553b142be upstream.
VTTBR_BADDR_MASK is used to sanity check the size and alignment of the
VTTBR address. It seems to currently be off by one, thereby only
allowing up to 39-bit addresses (instead of 40-bit) and also
insufficiently checking the alignment. This patch fixes it.
This patch is the 32bit pendent of Kristina's arm64 fix, and
she deserves the actual kudos for pinpointing that one.
Fixes: f7ed45be3b ("KVM: ARM: World-switch implementation")
Reported-by: Kristina Martsenko <kristina.martsenko@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 26aa7b3b1c upstream.
VTTBR_BADDR_MASK is used to sanity check the size and alignment of the
VTTBR address. It seems to currently be off by one, thereby only
allowing up to 47-bit addresses (instead of 48-bit) and also
insufficiently checking the alignment. This patch fixes it.
As an example, with 4k pages, before this patch we have:
PHYS_MASK_SHIFT = 48
VTTBR_X = 37 - 24 = 13
VTTBR_BADDR_SHIFT = 13 - 1 = 12
VTTBR_BADDR_MASK = ((1 << 35) - 1) << 12 = 0x00007ffffffff000
Which is wrong, because the mask doesn't allow bit 47 of the VTTBR
address to be set, and only requires the address to be 12-bit (4k)
aligned, while it actually needs to be 13-bit (8k) aligned because we
concatenate two 4k tables.
With this patch, the mask becomes 0x0000ffffffffe000, which is what we
want.
Fixes: 0369f6a34b ("arm64: KVM: EL2 register definitions")
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 9b8ae63798 upstream.
In case of instruction-decode failure or emulation failure,
x86_emulate_instruction() will call reexecute_instruction() which will
attempt to use the cr2 value passed to x86_emulate_instruction().
However, when x86_emulate_instruction() is called from
emulate_instruction(), cr2 is not passed (passed as 0) and therefore
it doesn't make sense to execute reexecute_instruction() logic at all.
Fixes: 51d8b66199 ("KVM: cleanup emulate_instruction")
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 1f4dcb3b21 upstream.
On this case, handle_emulation_failure() fills kvm_run with
internal-error information which it expects to be delivered
to user-mode for further processing.
However, the code reports a wrong return-value which makes KVM to never
return to user-mode on this scenario.
Fixes: 6d77dbfc88 ("KVM: inject #UD if instruction emulation fails and exit to
userspace")
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 61cb57c9ed upstream.
Instruction emulation after trapping a #UD exception can result in an
MMIO access, for example when emulating a MOVBE on a processor that
doesn't support the instruction. In this case, the #UD vmexit handler
must exit to user mode, but there wasn't any code to do so. Add it for
both VMX and SVM.
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This finally resolve crash if loaded under qemu + haxm. Haitao Shan pointed
out that the reason of that crash is that NX bit get set for page tables.
It seems we missed checking if _PAGE_NX is supported in kaiser_add_user_map
Link: https://www.spinics.net/lists/kernel/msg2689835.html
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Lepton Wu <ytht.net@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(backported from Greg K-H's 4.4 stable-queue)
Signed-off-by: Juerg Haefliger <juerg.haefliger@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit d51953b087 upstream.
This build failure triggers on 64-bit allmodconfig:
arch/x86/platform/uv/uv_nmi.c:493:2: error: implicit declaration of function ‘clocksource_touch_watchdog’ [-Werror=implicit-function-declaration]
which is caused by recent changes exposing a missing clocksource.h include
in uv_nmi.c:
cc1e24fdb0 x86/vdso: Remove pvclock fixmap machinery
this file got clocksource.h indirectly via fixmap.h - that stealth route
of header inclusion is now gone.
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
