commit 7f8998c7aef3ac9c5f3f2943e083dfa6302e90d0 upstream.
The different architectures used their own (and different) declarations:
extern __visible const void __nosave_begin, __nosave_end;
extern const void __nosave_begin, __nosave_end;
extern long __nosave_begin, __nosave_end;
Consolidate them using the first variant in <asm/sections.h>.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a843d00d038b11267279e3b5388222320f9ddc1d upstream. We found that TLB mismatch not only happens after kernel resume, but also happens during snapshot restore. So move it to the beginning of swsusp_arch_suspend(). Signed-off-by: Huacai Chen <chenhc@lemote.com> Cc: Steven J. Hill <Steven.Hill@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Patchwork: https://patchwork.linux-mips.org/patch/9621/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream.
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.
That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works. However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.
In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV. And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.
However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space. And user space really
expected SIGSEGV, not SIGBUS.
To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it. They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.
This is the mindless minimal patch to do this. A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.
Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.
Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[shengyong: Backport to 3.14
- adjust context
- ignore modification for arch nios2, because 3.14 does not support it
- add SIGSEGV handling to powerpc/cell spu_fault.c, because 3.14 does not
separate it to copro_fault.c
- add SIGSEGV handling to mm/memory.c, because 3.14 does not separate it
to gup.c
]
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b3cffac04eca9af46e1e23560a8ee22b1bd36d43 upstream.
Currently the guest exit trace event saves the VCPU pointer to the
structure, and the guest PC is retrieved by dereferencing it when the
event is printed rather than directly from the trace record. This isn't
safe as the printing may occur long afterwards, after the PC has changed
and potentially after the VCPU has been freed. Usually this results in
the same (wrong) PC being printed for multiple trace events. It also
isn't portable as userland has no way to access the VCPU data structure
when interpreting the trace record itself.
Lets save the actual PC in the structure so that the correct value is
accessible later.
Fixes: 669e846e6c4e ("KVM/MIPS32: MIPS arch specific APIs for KVM")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f798217dfd038af981a18bbe4bc57027a08bb182 upstream. The FPU and DSP are enabled via the CP0 Status CU1 and MX bits by kvm_mips_set_c0_status() on a guest exit, presumably in case there is active state that needs saving if pre-emption occurs. However neither of these bits are cleared again when returning to the guest. This effectively gives the guest access to the FPU/DSP hardware after the first guest exit even though it is not aware of its presence, allowing FP instructions in guest user code to intermittently actually execute instead of trapping into the guest OS for emulation. It will then read & manipulate the hardware FP registers which technically belong to the user process (e.g. QEMU), or are stale from another user process. It can also crash the guest OS by causing an FP exception, for which a guest exception handler won't have been registered. First lets save and disable the FPU (and MSA) state with lose_fpu(1) before entering the guest. This simplifies the problem, especially for when guest FPU/MSA support is added in the future, and prevents FR=1 FPU state being live when the FR bit gets cleared for the guest, which according to the architecture causes the contents of the FPU and vector registers to become UNPREDICTABLE. We can then safely remove the enabling of the FPU in kvm_mips_set_c0_status(), since there should never be any active FPU or MSA state to save at pre-emption, which should plug the FPU leak. DSP state is always live rather than being lazily restored, so for that it is simpler to just clear the MX bit again when re-entering the guest. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Sanjay Lal <sanjayl@kymasys.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # v3.10+: 044f0f03eca0: MIPS: KVM: Deliver guest interrupts Cc: <stable@vger.kernel.org> # v3.10+ Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 044f0f03eca0110e1835b2ea038a484b93950328 upstream. When about to run the guest, deliver guest interrupts after disabling host interrupts. This should prevent an hrtimer interrupt from being handled after delivering guest interrupts, and therefore not delivering the guest timer interrupt until after the next guest exit. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: Sanjay Lal <sanjayl@kymasys.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3ce465e04bfd8de9956d515d6e9587faac3375dc upstream.
Export the _save_fp asm function used by the lose_fpu(1) macro to GPL
modules so that KVM can make use of it when it is built as a module.
This fixes the following build error when CONFIG_KVM=m due to commit
f798217dfd03 ("KVM: MIPS: Don't leak FPU/DSP to guest"):
ERROR: "_save_fp" [arch/mips/kvm/kvm.ko] undefined!
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Fixes: f798217dfd03 (KVM: MIPS: Don't leak FPU/DSP to guest)
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9260/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[james.hogan@imgtec.com: Only export when CPU_R4K_FPU=y prior to v3.16,
so as not to break the Octeon build which excludes FPU support. KVM
depends on MIPS32r2 anyway.]
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c7754e75100ed5e3068ac5085747f2bfc386c8d6 upstream. As printk() invocation can cause e.g. a TLB miss, printk() cannot be called before the exception handlers have been properly initialized. This can happen e.g. when netconsole has been loaded as a kernel module and the TLB table has been cleared when a CPU was offline. Call cpu_report() in start_secondary() only after the exception handlers have been initialized to fix this. Without the patch the kernel will randomly either lockup or crash after a CPU is onlined and the console driver is a module. Signed-off-by: Hemmo Nieminen <hemmo.nieminen@iki.fi> Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Cc: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/8953/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 63a87fe0d0de2ce126a8cec9a299a133cfd5658e upstream. octeon_cpu_disable() will unconditionally enable interrupts when called. We can assume that the routine is always called with interrupts disabled, so just delete the incorrect local_irq_disable/enable(). The patch fixes the following crash when offlining a CPU: [ 93.818785] ------------[ cut here ]------------ [ 93.823421] WARNING: CPU: 1 PID: 10 at kernel/smp.c:231 flush_smp_call_function_queue+0x1c4/0x1d0() [ 93.836215] Modules linked in: [ 93.839287] CPU: 1 PID: 10 Comm: migration/1 Not tainted 3.19.0-rc4-octeon-los_b5f0 #1 [ 93.847212] Stack : 0000000000000001 ffffffff81b2cf90 0000000000000004 ffffffff81630000 0000000000000000 0000000000000000 0000000000000000 000000000000004a 0000000000000006 ffffffff8117e550 0000000000000000 0000000000000000 ffffffff81b30000 ffffffff81b26808 8000000032c77748 ffffffff81627e07 ffffffff81595ec8 ffffffff81b26808 000000000000000a 0000000000000001 0000000000000001 0000000000000003 0000000010008ce1 ffffffff815030c8 8000000032cbbb38 ffffffff8113d42c 0000000010008ce1 ffffffff8117f36c 8000000032c77300 8000000032cbba50 0000000000000001 ffffffff81503984 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ffffffff81121668 0000000000000000 0000000000000000 ... [ 93.912819] Call Trace: [ 93.915273] [<ffffffff81121668>] show_stack+0x68/0x80 [ 93.920335] [<ffffffff81503984>] dump_stack+0x6c/0x90 [ 93.925395] [<ffffffff8113d58c>] warn_slowpath_common+0x94/0xd8 [ 93.931324] [<ffffffff811a402c>] flush_smp_call_function_queue+0x1c4/0x1d0 [ 93.938208] [<ffffffff811a4128>] hotplug_cfd+0xf0/0x108 [ 93.943444] [<ffffffff8115bacc>] notifier_call_chain+0x5c/0xb8 [ 93.949286] [<ffffffff8113d704>] cpu_notify+0x24/0x60 [ 93.954348] [<ffffffff81501738>] take_cpu_down+0x38/0x58 [ 93.959670] [<ffffffff811b343c>] multi_cpu_stop+0x154/0x180 [ 93.965250] [<ffffffff811b3768>] cpu_stopper_thread+0xd8/0x160 [ 93.971093] [<ffffffff8115ea4c>] smpboot_thread_fn+0x1ec/0x1f8 [ 93.976936] [<ffffffff8115ab04>] kthread+0xd4/0xf0 [ 93.981735] [<ffffffff8111c4f0>] ret_from_kernel_thread+0x14/0x1c [ 93.987835] [ 93.989326] ---[ end trace c9e3815ee655bda9 ]--- [ 93.993951] Kernel bug detected[#1]: [ 93.997533] CPU: 1 PID: 10 Comm: migration/1 Tainted: G W 3.19.0-rc4-octeon-los_b5f0 #1 [ 94.006591] task: 8000000032c77300 ti: 8000000032cb8000 task.ti: 8000000032cb8000 [ 94.014081] $ 0 : 0000000000000000 0000000010000ce1 0000000000000001 ffffffff81620000 [ 94.022146] $ 4 : 8000000002c72ac0 0000000000000000 00000000000001a7 ffffffff813b06f0 [ 94.030210] $ 8 : ffffffff813b20d8 0000000000000000 0000000000000000 ffffffff81630000 [ 94.038275] $12 : 0000000000000087 0000000000000000 0000000000000086 0000000000000000 [ 94.046339] $16 : ffffffff81623168 0000000000000001 0000000000000000 0000000000000008 [ 94.054405] $20 : 0000000000000001 0000000000000001 0000000000000001 0000000000000003 [ 94.062470] $24 : 0000000000000038 ffffffff813b7f10 [ 94.070536] $28 : 8000000032cb8000 8000000032cbbc20 0000000010008ce1 ffffffff811bcaf4 [ 94.078601] Hi : 0000000000f188e8 [ 94.082179] Lo : d4fdf3b646c09d55 [ 94.085760] epc : ffffffff811bc9d0 irq_work_run_list+0x8/0xf8 [ 94.091686] Tainted: G W [ 94.095613] ra : ffffffff811bcaf4 irq_work_run+0x34/0x60 [ 94.101192] Status: 10000ce3 KX SX UX KERNEL EXL IE [ 94.106235] Cause : 40808034 [ 94.109119] PrId : 000d9301 (Cavium Octeon II) [ 94.113653] Modules linked in: [ 94.116721] Process migration/1 (pid: 10, threadinfo=8000000032cb8000, task=8000000032c77300, tls=0000000000000000) [ 94.127168] Stack : 8000000002c74c80 ffffffff811a4128 0000000000000001 ffffffff81635720 fffffffffffffff2 ffffffff8115bacc 80000000320fbce0 80000000320fbca4 80000000320fbc80 0000000000000002 0000000000000004 ffffffff8113d704 80000000320fbce0 ffffffff81501738 0000000000000003 ffffffff811b343c 8000000002c72aa0 8000000002c72aa8 ffffffff8159cae8 ffffffff8159caa0 ffffffff81650000 80000000320fbbf0 80000000320fbc80 ffffffff811b32e8 0000000000000000 ffffffff811b3768 ffffffff81622b80 ffffffff815148a8 8000000032c77300 8000000002c73e80 ffffffff815148a8 8000000032c77300 ffffffff81622b80 ffffffff815148a8 8000000032c77300 ffffffff81503f48 ffffffff8115ea0c ffffffff81620000 0000000000000000 ffffffff81174d64 ... [ 94.192771] Call Trace: [ 94.195222] [<ffffffff811bc9d0>] irq_work_run_list+0x8/0xf8 [ 94.200802] [<ffffffff811bcaf4>] irq_work_run+0x34/0x60 [ 94.206036] [<ffffffff811a4128>] hotplug_cfd+0xf0/0x108 [ 94.211269] [<ffffffff8115bacc>] notifier_call_chain+0x5c/0xb8 [ 94.217111] [<ffffffff8113d704>] cpu_notify+0x24/0x60 [ 94.222171] [<ffffffff81501738>] take_cpu_down+0x38/0x58 [ 94.227491] [<ffffffff811b343c>] multi_cpu_stop+0x154/0x180 [ 94.233072] [<ffffffff811b3768>] cpu_stopper_thread+0xd8/0x160 [ 94.238914] [<ffffffff8115ea4c>] smpboot_thread_fn+0x1ec/0x1f8 [ 94.244757] [<ffffffff8115ab04>] kthread+0xd4/0xf0 [ 94.249555] [<ffffffff8111c4f0>] ret_from_kernel_thread+0x14/0x1c [ 94.255654] [ 94.257146] Code: a2423c40 40026000 30420001 <00020336> dc820000 10400037 00000000 0000010f 0000010f [ 94.267183] ---[ end trace c9e3815ee655bdaa ]--- [ 94.271804] Fatal exception: panic in 5 seconds Reported-by: Hemmo Nieminen <hemmo.nieminen@iki.fi> Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/8952/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a3e6c1eff54878506b2dddcc202df9cc8180facb upstream. If the irq_chip does not define .irq_disable, any call to disable_irq will defer disabling the IRQ until it fires while marked as disabled. This assumes that the handler function checks for this condition, which handle_percpu_irq does not. In this case, calling disable_irq leads to an IRQ storm, if the interrupt fires while disabled. This optimization is only useful when disabling the IRQ is slow, which is not true for the MIPS CPU IRQ. Disable this optimization by implementing .irq_disable and .irq_enable Signed-off-by: Felix Fietkau <nbd@openwrt.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8949/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>