* Re: [PATCH 1/1] powerpc/iommu: Enable remaining IOMMU Pagesizes present in LoPAR
From: Alexey Kardashevskiy @ 2021-03-23 7:41 UTC (permalink / raw)
To: Leonardo Bras, Michael Ellerman, Benjamin Herrenschmidt,
Paul Mackerras, Christophe Leroy, Joel Stanley, brking
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <20210322190943.715368-1-leobras.c@gmail.com>
On 23/03/2021 06:09, Leonardo Bras wrote:
> According to LoPAR, ibm,query-pe-dma-window output named "IO Page Sizes"
> will let the OS know all possible pagesizes that can be used for creating a
> new DDW.
>
> Currently Linux will only try using 3 of the 8 available options:
> 4K, 64K and 16M. According to LoPAR, Hypervisor may also offer 32M, 64M,
> 128M, 256M and 16G.
>
> Enabling bigger pages would be interesting for direct mapping systems
> with a lot of RAM, while using less TCE entries.
> > Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
> ---
> arch/powerpc/include/asm/iommu.h | 8 ++++++++
> arch/powerpc/platforms/pseries/iommu.c | 28 +++++++++++++++++++-------
> 2 files changed, 29 insertions(+), 7 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
> index deef7c94d7b6..c170048b7a1b 100644
> --- a/arch/powerpc/include/asm/iommu.h
> +++ b/arch/powerpc/include/asm/iommu.h
> @@ -19,6 +19,14 @@
> #include <asm/pci-bridge.h>
> #include <asm/asm-const.h>
>
> +#define IOMMU_PAGE_SHIFT_16G 34
> +#define IOMMU_PAGE_SHIFT_256M 28
> +#define IOMMU_PAGE_SHIFT_128M 27
> +#define IOMMU_PAGE_SHIFT_64M 26
> +#define IOMMU_PAGE_SHIFT_32M 25
> +#define IOMMU_PAGE_SHIFT_16M 24
> +#define IOMMU_PAGE_SHIFT_64K 16
These are not very descriptive, these are just normal shifts, could be
as simple as __builtin_ctz(SZ_4K) (gcc will optimize this) and so on.
OTOH the PAPR page sizes need macros as they are the ones which are
weird and screaming for macros.
I'd steal/rework spapr_page_mask_to_query_mask() from QEMU. Thanks,
> +
> #define IOMMU_PAGE_SHIFT_4K 12
> #define IOMMU_PAGE_SIZE_4K (ASM_CONST(1) << IOMMU_PAGE_SHIFT_4K)
> #define IOMMU_PAGE_MASK_4K (~((1 << IOMMU_PAGE_SHIFT_4K) - 1))
> diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
> index 9fc5217f0c8e..02958e80aa91 100644
> --- a/arch/powerpc/platforms/pseries/iommu.c
> +++ b/arch/powerpc/platforms/pseries/iommu.c
> @@ -1099,6 +1099,24 @@ static void reset_dma_window(struct pci_dev *dev, struct device_node *par_dn)
> ret);
> }
>
> +/* Returns page shift based on "IO Page Sizes" output at ibm,query-pe-dma-window. SeeL LoPAR */
> +static int iommu_get_page_shift(u32 query_page_size)
> +{
> + const int shift[] = {IOMMU_PAGE_SHIFT_4K, IOMMU_PAGE_SHIFT_64K, IOMMU_PAGE_SHIFT_16M,
> + IOMMU_PAGE_SHIFT_32M, IOMMU_PAGE_SHIFT_64M, IOMMU_PAGE_SHIFT_128M,
> + IOMMU_PAGE_SHIFT_256M, IOMMU_PAGE_SHIFT_16G};
> + int i = ARRAY_SIZE(shift) - 1;
> +
> + /* Looks for the largest page size supported */
> + for (; i >= 0; i--) {
> + if (query_page_size & (1 << i))
> + return shift[i];
> + }
> +
> + /* No valid page size found. */
> + return 0;
> +}
> +
> /*
> * If the PE supports dynamic dma windows, and there is space for a table
> * that can map all pages in a linear offset, then setup such a table,
> @@ -1206,13 +1224,9 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn)
> goto out_failed;
> }
> }
> - if (query.page_size & 4) {
> - page_shift = 24; /* 16MB */
> - } else if (query.page_size & 2) {
> - page_shift = 16; /* 64kB */
> - } else if (query.page_size & 1) {
> - page_shift = 12; /* 4kB */
> - } else {
> +
> + page_shift = iommu_get_page_shift(query.page_size);
> + if (!page_shift) {
> dev_dbg(&dev->dev, "no supported direct page size in mask %x",
> query.page_size);
> goto out_failed;
>
--
Alexey
^ permalink raw reply
* Re: [RFC Qemu PATCH v2 1/2] spapr: drc: Add support for async hcalls at the drc level
From: Shivaprasad G Bhat @ 2021-03-23 7:53 UTC (permalink / raw)
To: David Gibson
Cc: xiaoguangrong.eric, mst, aneesh.kumar, linux-nvdimm, qemu-devel,
kvm-ppc, Greg Kurz, shivaprasadbhat, qemu-ppc, bharata, imammedo,
linuxppc-dev
In-Reply-To: <20210208062122.GA40668@yekko.fritz.box>
Hi David,
Sorry about the delay.
On 2/8/21 11:51 AM, David Gibson wrote:
> On Tue, Jan 19, 2021 at 12:40:31PM +0530, Shivaprasad G Bhat wrote:
>> Thanks for the comments!
>>
>>
>> On 12/28/20 2:08 PM, David Gibson wrote:
>>
>>> On Mon, Dec 21, 2020 at 01:08:53PM +0100, Greg Kurz wrote:
>> ...
>>>> The overall idea looks good but I think you should consider using
>>>> a thread pool to implement it. See below.
>>> I am not convinced, however. Specifically, attaching this to the DRC
>>> doesn't make sense to me. We're adding exactly one DRC related async
>>> hcall, and I can't really see much call for another one. We could
>>> have other async hcalls - indeed we already have one for HPT resizing
>>> - but attaching this to DRCs doesn't help for those.
>> The semantics of the hcall made me think, if this is going to be
>> re-usable for future if implemented at DRC level.
> It would only be re-usable for operations that are actually connected
> to DRCs. It doesn't seem to me particularly likely that we'll ever
> have more asynchronous hcalls that are also associated with DRCs.
Okay
>> Other option
>> is to move the async-hcall-state/list into the NVDIMMState structure
>> in include/hw/mem/nvdimm.h and handle it with machine->nvdimms_state
>> at a global level.
> I'm ok with either of two options:
>
> A) Implement this ad-hoc for this specific case, making whatever
> simplifications you can based on this specific case.
I am simplifying it to nvdimm use-case alone and limiting the scope.
> B) Implement a general mechanism for async hcalls that is *not* tied
> to DRCs. Then use that for the existing H_RESIZE_HPT_PREPARE call as
> well as this new one.
>
>> Hope you are okay with using the pool based approach that Greg
> Honestly a thread pool seems like it might be overkill for this
> application.
I think its appropriate here as that is what is being done by virtio-pmem
too for flush requests. The aio infrastructure simplifies lot of the
thread handling usage. Please suggest if you think there are better ways.
I am sending the next version addressing all the comments from you and Greg.
Thanks,
Shivaprasad
^ permalink raw reply
* Re: [PATCH v4 04/46] KVM: PPC: Book3S HV: Prevent radix guests from setting LPCR[TC]
From: Alexey Kardashevskiy @ 2021-03-23 8:36 UTC (permalink / raw)
To: Nicholas Piggin, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <20210323010305.1045293-5-npiggin@gmail.com>
On 23/03/2021 12:02, Nicholas Piggin wrote:
> This bit only applies to hash partitions.
>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> ---
> arch/powerpc/kvm/book3s_hv.c | 6 ++++++
> arch/powerpc/kvm/book3s_hv_nested.c | 3 +--
> 2 files changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index c5de7e3f22b6..1ffb0902e779 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -1645,6 +1645,12 @@ static int kvm_arch_vcpu_ioctl_set_sregs_hv(struct kvm_vcpu *vcpu,
> */
> unsigned long kvmppc_filter_lpcr_hv(struct kvmppc_vcore *vc, unsigned long lpcr)
> {
> + struct kvm *kvm = vc->kvm;
> +
> + /* LPCR_TC only applies to HPT guests */
> + if (kvm_is_radix(kvm))
> + lpcr &= ~LPCR_TC;
> +
> /* On POWER8 and above, userspace can modify AIL */
> if (!cpu_has_feature(CPU_FTR_ARCH_207S))
> lpcr &= ~LPCR_AIL;
> diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c
> index f7b441b3eb17..851e3f527eb2 100644
> --- a/arch/powerpc/kvm/book3s_hv_nested.c
> +++ b/arch/powerpc/kvm/book3s_hv_nested.c
> @@ -140,8 +140,7 @@ static void sanitise_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr)
> /*
> * Don't let L1 change LPCR bits for the L2 except these:
> */
> - mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD |
> - LPCR_LPES | LPCR_MER;
> + mask = LPCR_DPFD | LPCR_ILE | LPCR_AIL | LPCR_LD | LPCR_LPES | LPCR_MER;
> hr->lpcr = kvmppc_filter_lpcr_hv(vc,
> (vc->lpcr & ~mask) | (hr->lpcr & mask));
>
>
--
Alexey
^ permalink raw reply
* Re: [PATCH v4 22/46] KVM: PPC: Book3S HV P9: Stop handling hcalls in real-mode in the P9 path
From: Alexey Kardashevskiy @ 2021-03-23 9:02 UTC (permalink / raw)
To: Nicholas Piggin, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <20210323010305.1045293-23-npiggin@gmail.com>
On 23/03/2021 12:02, Nicholas Piggin wrote:
> In the interest of minimising the amount of code that is run in
> "real-mode", don't handle hcalls in real mode in the P9 path.
>
> POWER8 and earlier are much more expensive to exit from HV real mode
> and switch to host mode, because on those processors HV interrupts get
> to the hypervisor with the MMU off, and the other threads in the core
> need to be pulled out of the guest, and SLBs all need to be saved,
> ERATs invalidated, and host SLB reloaded before the MMU is re-enabled
> in host mode. Hash guests also require a lot of hcalls to run. The
> XICS interrupt controller requires hcalls to run.
>
> By contrast, POWER9 has independent thread switching, and in radix mode
> the hypervisor is already in a host virtual memory mode when the HV
> interrupt is taken. Radix + xive guests don't need hcalls to handle
> interrupts or manage translations.
>
> So it's much less important to handle hcalls in real mode in P9.
>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
> arch/powerpc/include/asm/kvm_ppc.h | 5 ++
> arch/powerpc/kvm/book3s_hv.c | 57 ++++++++++++++++----
> arch/powerpc/kvm/book3s_hv_rmhandlers.S | 5 ++
> arch/powerpc/kvm/book3s_xive.c | 70 +++++++++++++++++++++++++
> 4 files changed, 127 insertions(+), 10 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
> index 73b1ca5a6471..db6646c2ade2 100644
> --- a/arch/powerpc/include/asm/kvm_ppc.h
> +++ b/arch/powerpc/include/asm/kvm_ppc.h
> @@ -607,6 +607,7 @@ extern void kvmppc_free_pimap(struct kvm *kvm);
> extern int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall);
> extern void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu);
> extern int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd);
> +extern int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req);
> extern u64 kvmppc_xics_get_icp(struct kvm_vcpu *vcpu);
> extern int kvmppc_xics_set_icp(struct kvm_vcpu *vcpu, u64 icpval);
> extern int kvmppc_xics_connect_vcpu(struct kvm_device *dev,
> @@ -639,6 +640,8 @@ static inline int kvmppc_xics_enabled(struct kvm_vcpu *vcpu)
> static inline void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu) { }
> static inline int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd)
> { return 0; }
> +static inline int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req)
> + { return 0; }
> #endif
>
> #ifdef CONFIG_KVM_XIVE
> @@ -673,6 +676,7 @@ extern int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq,
> int level, bool line_status);
> extern void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu);
> extern void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu);
> +extern void kvmppc_xive_cede_vcpu(struct kvm_vcpu *vcpu);
>
> static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
> {
> @@ -714,6 +718,7 @@ static inline int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 ir
> int level, bool line_status) { return -ENODEV; }
> static inline void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu) { }
> static inline void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu) { }
> +static inline void kvmppc_xive_cede_vcpu(struct kvm_vcpu *vcpu) { }
>
> static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
> { return 0; }
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index fa7614c37e08..17739aaee3d8 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -1142,12 +1142,13 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
> }
>
> /*
> - * Handle H_CEDE in the nested virtualization case where we haven't
> - * called the real-mode hcall handlers in book3s_hv_rmhandlers.S.
> + * Handle H_CEDE in the P9 path where we don't call the real-mode hcall
> + * handlers in book3s_hv_rmhandlers.S.
> + *
> * This has to be done early, not in kvmppc_pseries_do_hcall(), so
> * that the cede logic in kvmppc_run_single_vcpu() works properly.
> */
> -static void kvmppc_nested_cede(struct kvm_vcpu *vcpu)
> +static void kvmppc_cede(struct kvm_vcpu *vcpu)
> {
> vcpu->arch.shregs.msr |= MSR_EE;
> vcpu->arch.ceded = 1;
> @@ -1403,9 +1404,15 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu,
> /* hcall - punt to userspace */
> int i;
>
> - /* hypercall with MSR_PR has already been handled in rmode,
> - * and never reaches here.
> - */
> + if (unlikely(vcpu->arch.shregs.msr & MSR_PR)) {
> + /*
> + * Guest userspace executed sc 1, reflect it back as a
> + * privileged program check interrupt.
> + */
> + kvmppc_core_queue_program(vcpu, SRR1_PROGPRIV);
> + r = RESUME_GUEST;
> + break;
> + }
>
> run->papr_hcall.nr = kvmppc_get_gpr(vcpu, 3);
> for (i = 0; i < 9; ++i)
> @@ -3663,6 +3670,12 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit,
> return trap;
> }
>
> +static inline bool hcall_is_xics(unsigned long req)
> +{
> + return (req == H_EOI || req == H_CPPR || req == H_IPI ||
> + req == H_IPOLL || req == H_XIRR || req == H_XIRR_X);
Do not need braces :)
> +}
> +
> /*
> * Virtual-mode guest entry for POWER9 and later when the host and
> * guest are both using the radix MMU. The LPIDR has already been set.
> @@ -3774,15 +3787,36 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
> /* H_CEDE has to be handled now, not later */
> if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
> kvmppc_get_gpr(vcpu, 3) == H_CEDE) {
> - kvmppc_nested_cede(vcpu);
> + kvmppc_cede(vcpu);
> kvmppc_set_gpr(vcpu, 3, 0);
> trap = 0;
> }
> } else {
> kvmppc_xive_push_vcpu(vcpu);
> trap = kvmhv_load_hv_regs_and_go(vcpu, time_limit, lpcr);
> + if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
> + !(vcpu->arch.shregs.msr & MSR_PR)) {
> + unsigned long req = kvmppc_get_gpr(vcpu, 3);
> +
> + /* H_CEDE has to be handled now, not later */
> + if (req == H_CEDE) {
> + kvmppc_cede(vcpu);
> + kvmppc_xive_cede_vcpu(vcpu); /* may un-cede */
> + kvmppc_set_gpr(vcpu, 3, 0);
> + trap = 0;
> +
> + /* XICS hcalls must be handled before xive is pulled */
> + } else if (hcall_is_xics(req)) {
> + int ret;
> +
> + ret = kvmppc_xive_xics_hcall(vcpu, req);
> + if (ret != H_TOO_HARD) {
> + kvmppc_set_gpr(vcpu, 3, ret);
> + trap = 0;
> + }
> + }
> + }
> kvmppc_xive_pull_vcpu(vcpu);
> -
> }
>
> vcpu->arch.slb_max = 0;
> @@ -4442,8 +4476,11 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu)
> else
> r = kvmppc_run_vcpu(vcpu);
>
> - if (run->exit_reason == KVM_EXIT_PAPR_HCALL &&
> - !(vcpu->arch.shregs.msr & MSR_PR)) {
> + if (run->exit_reason == KVM_EXIT_PAPR_HCALL) {
> + if (WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_PR)) {
> + r = RESUME_GUEST;
> + continue;
> + }
> trace_kvm_hcall_enter(vcpu);
> r = kvmppc_pseries_do_hcall(vcpu);
> trace_kvm_hcall_exit(vcpu, r);
> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> index c11597f815e4..2d0d14ed1d92 100644
> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> @@ -1397,9 +1397,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
> mr r4,r9
> bge fast_guest_return
> 2:
> + /* If we came in through the P9 short path, no real mode hcalls */
> + lwz r0, STACK_SLOT_SHORT_PATH(r1)
> + cmpwi r0, 0
> + bne no_try_real
btw is mmu on at this point? or it gets enabled by rfid at the end of
guest_exit_short_path?
anyway,
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> /* See if this is an hcall we can handle in real mode */
> cmpwi r12,BOOK3S_INTERRUPT_SYSCALL
> beq hcall_try_real_mode
> +no_try_real:
>
> /* Hypervisor doorbell - exit only if host IPI flag set */
> cmpwi r12, BOOK3S_INTERRUPT_H_DOORBELL
> diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c
> index 741bf1f4387a..dcc07ceaf5ca 100644
> --- a/arch/powerpc/kvm/book3s_xive.c
> +++ b/arch/powerpc/kvm/book3s_xive.c
> @@ -158,6 +158,40 @@ void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu)
> }
> EXPORT_SYMBOL_GPL(kvmppc_xive_pull_vcpu);
>
> +void kvmppc_xive_cede_vcpu(struct kvm_vcpu *vcpu)
> +{
> + void __iomem *esc_vaddr = (void __iomem *)vcpu->arch.xive_esc_vaddr;
> +
> + if (!esc_vaddr)
> + return;
> +
> + /* we are using XIVE with single escalation */
> +
> + if (vcpu->arch.xive_esc_on) {
> + /*
> + * If we still have a pending escalation, abort the cede,
> + * and we must set PQ to 10 rather than 00 so that we don't
> + * potentially end up with two entries for the escalation
> + * interrupt in the XIVE interrupt queue. In that case
> + * we also don't want to set xive_esc_on to 1 here in
> + * case we race with xive_esc_irq().
> + */
> + vcpu->arch.ceded = 0;
> + /*
> + * The escalation interrupts are special as we don't EOI them.
> + * There is no need to use the load-after-store ordering offset
> + * to set PQ to 10 as we won't use StoreEOI.
> + */
> + __raw_readq(esc_vaddr + XIVE_ESB_SET_PQ_10);
> + } else {
> + vcpu->arch.xive_esc_on = true;
> + mb();
> + __raw_readq(esc_vaddr + XIVE_ESB_SET_PQ_00);
> + }
> + mb();
> +}
> +EXPORT_SYMBOL_GPL(kvmppc_xive_cede_vcpu);
> +
> /*
> * This is a simple trigger for a generic XIVE IRQ. This must
> * only be called for interrupts that support a trigger page
> @@ -2106,6 +2140,42 @@ static int kvmppc_xive_create(struct kvm_device *dev, u32 type)
> return 0;
> }
>
> +int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req)
> +{
> + struct kvmppc_vcore *vc = vcpu->arch.vcore;
> +
> + /*
> + * This test covers the case in which a vCPU does XICS hcalls without
> + * QEMU having connected the vCPU to a XICS ICP. The ICP is the KVM
> + * XICS device on P8 or XICS-on-XIVE on P9. It catches QEMU errors when
> + * the interrupt mode is negotiated, we don't want the OS to do XICS
> + * hcalls after having negotiated the XIVE interrupt mode.
> + */
> + if (!kvmppc_xics_enabled(vcpu))
> + return H_TOO_HARD;
> +
> + switch (req) {
> + case H_XIRR:
> + return xive_vm_h_xirr(vcpu);
> + case H_CPPR:
> + return xive_vm_h_cppr(vcpu, kvmppc_get_gpr(vcpu, 4));
> + case H_EOI:
> + return xive_vm_h_eoi(vcpu, kvmppc_get_gpr(vcpu, 4));
> + case H_IPI:
> + return xive_vm_h_ipi(vcpu, kvmppc_get_gpr(vcpu, 4),
> + kvmppc_get_gpr(vcpu, 5));
> + case H_IPOLL:
> + return xive_vm_h_ipoll(vcpu, kvmppc_get_gpr(vcpu, 4));
> + case H_XIRR_X:
> + xive_vm_h_xirr(vcpu);
> + kvmppc_set_gpr(vcpu, 5, get_tb() + vc->tb_offset);
> + return H_SUCCESS;
> + }
> +
> + return H_UNSUPPORTED;
> +}
> +EXPORT_SYMBOL_GPL(kvmppc_xive_xics_hcall);
> +
> int kvmppc_xive_debug_show_queues(struct seq_file *m, struct kvm_vcpu *vcpu)
> {
> struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
>
--
Alexey
^ permalink raw reply
* [PATCH v2 -next] powerpc: kernel/time.c - cleanup warnings
From: He Ying @ 2021-03-23 9:12 UTC (permalink / raw)
To: mpe, benh, paulus, a.zummo, alexandre.belloni, christophe.leroy,
npiggin, msuchanek, heying24, tglx, peterz, geert+renesas,
kernelfans, frederic
Cc: linux-rtc, linuxppc-dev, linux-kernel
We found these warnings in arch/powerpc/kernel/time.c as follows:
warning: symbol 'decrementer_max' was not declared. Should it be static?
warning: symbol 'rtc_lock' was not declared. Should it be static?
warning: symbol 'dtl_consumer' was not declared. Should it be static?
Declare 'decrementer_max' and 'rtc_lock' in powerpc asm/time.h.
Rename 'rtc_lock' in drviers/rtc/rtc-vr41xx.c to 'vr41xx_rtc_lock' to
avoid the conflict with the variable in powerpc asm/time.h.
Move 'dtl_consumer' definition behind "include <asm/dtl.h>" because it
is declared there.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: He Ying <heying24@huawei.com>
---
v2:
- Instead of including linux/mc146818rtc.h in powerpc kernel/time.c, declare
rtc_lock in powerpc asm/time.h.
arch/powerpc/include/asm/time.h | 3 +++
arch/powerpc/kernel/time.c | 6 ++----
drivers/rtc/rtc-vr41xx.c | 22 +++++++++++-----------
3 files changed, 16 insertions(+), 15 deletions(-)
diff --git a/arch/powerpc/include/asm/time.h b/arch/powerpc/include/asm/time.h
index 8dd3cdb25338..64a3ef0b4270 100644
--- a/arch/powerpc/include/asm/time.h
+++ b/arch/powerpc/include/asm/time.h
@@ -12,6 +12,7 @@
#ifdef __KERNEL__
#include <linux/types.h>
#include <linux/percpu.h>
+#include <linux/spinlock.h>
#include <asm/processor.h>
#include <asm/cpu_has_feature.h>
@@ -22,6 +23,8 @@ extern unsigned long tb_ticks_per_jiffy;
extern unsigned long tb_ticks_per_usec;
extern unsigned long tb_ticks_per_sec;
extern struct clock_event_device decrementer_clockevent;
+extern u64 decrementer_max;
+extern spinlock_t rtc_lock;
extern void generic_calibrate_decr(void);
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index b67d93a609a2..60b6ac7d3685 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -150,10 +150,6 @@ bool tb_invalid;
u64 __cputime_usec_factor;
EXPORT_SYMBOL(__cputime_usec_factor);
-#ifdef CONFIG_PPC_SPLPAR
-void (*dtl_consumer)(struct dtl_entry *, u64);
-#endif
-
static void calc_cputime_factors(void)
{
struct div_result res;
@@ -179,6 +175,8 @@ static inline unsigned long read_spurr(unsigned long tb)
#include <asm/dtl.h>
+void (*dtl_consumer)(struct dtl_entry *, u64);
+
/*
* Scan the dispatch trace log and count up the stolen time.
* Should be called with interrupts disabled.
diff --git a/drivers/rtc/rtc-vr41xx.c b/drivers/rtc/rtc-vr41xx.c
index 5a9f9ad86d32..cc31db058197 100644
--- a/drivers/rtc/rtc-vr41xx.c
+++ b/drivers/rtc/rtc-vr41xx.c
@@ -72,7 +72,7 @@ static void __iomem *rtc2_base;
static unsigned long epoch = 1970; /* Jan 1 1970 00:00:00 */
-static DEFINE_SPINLOCK(rtc_lock);
+static DEFINE_SPINLOCK(vr41xx_rtc_lock);
static char rtc_name[] = "RTC";
static unsigned long periodic_count;
static unsigned int alarm_enabled;
@@ -101,13 +101,13 @@ static inline time64_t read_elapsed_second(void)
static inline void write_elapsed_second(time64_t sec)
{
- spin_lock_irq(&rtc_lock);
+ spin_lock_irq(&vr41xx_rtc_lock);
rtc1_write(ETIMELREG, (uint16_t)(sec << 15));
rtc1_write(ETIMEMREG, (uint16_t)(sec >> 1));
rtc1_write(ETIMEHREG, (uint16_t)(sec >> 17));
- spin_unlock_irq(&rtc_lock);
+ spin_unlock_irq(&vr41xx_rtc_lock);
}
static int vr41xx_rtc_read_time(struct device *dev, struct rtc_time *time)
@@ -139,14 +139,14 @@ static int vr41xx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
unsigned long low, mid, high;
struct rtc_time *time = &wkalrm->time;
- spin_lock_irq(&rtc_lock);
+ spin_lock_irq(&vr41xx_rtc_lock);
low = rtc1_read(ECMPLREG);
mid = rtc1_read(ECMPMREG);
high = rtc1_read(ECMPHREG);
wkalrm->enabled = alarm_enabled;
- spin_unlock_irq(&rtc_lock);
+ spin_unlock_irq(&vr41xx_rtc_lock);
rtc_time64_to_tm((high << 17) | (mid << 1) | (low >> 15), time);
@@ -159,7 +159,7 @@ static int vr41xx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
alarm_sec = rtc_tm_to_time64(&wkalrm->time);
- spin_lock_irq(&rtc_lock);
+ spin_lock_irq(&vr41xx_rtc_lock);
if (alarm_enabled)
disable_irq(aie_irq);
@@ -173,7 +173,7 @@ static int vr41xx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
alarm_enabled = wkalrm->enabled;
- spin_unlock_irq(&rtc_lock);
+ spin_unlock_irq(&vr41xx_rtc_lock);
return 0;
}
@@ -202,7 +202,7 @@ static int vr41xx_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long
static int vr41xx_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
- spin_lock_irq(&rtc_lock);
+ spin_lock_irq(&vr41xx_rtc_lock);
if (enabled) {
if (!alarm_enabled) {
enable_irq(aie_irq);
@@ -214,7 +214,7 @@ static int vr41xx_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
alarm_enabled = 0;
}
}
- spin_unlock_irq(&rtc_lock);
+ spin_unlock_irq(&vr41xx_rtc_lock);
return 0;
}
@@ -296,7 +296,7 @@ static int rtc_probe(struct platform_device *pdev)
rtc->range_max = (1ULL << 33) - 1;
rtc->max_user_freq = MAX_PERIODIC_RATE;
- spin_lock_irq(&rtc_lock);
+ spin_lock_irq(&vr41xx_rtc_lock);
rtc1_write(ECMPLREG, 0);
rtc1_write(ECMPMREG, 0);
@@ -304,7 +304,7 @@ static int rtc_probe(struct platform_device *pdev)
rtc1_write(RTCL1LREG, 0);
rtc1_write(RTCL1HREG, 0);
- spin_unlock_irq(&rtc_lock);
+ spin_unlock_irq(&vr41xx_rtc_lock);
aie_irq = platform_get_irq(pdev, 0);
if (aie_irq <= 0) {
--
2.17.1
^ permalink raw reply related
* Re: [PATCH v4 22/46] KVM: PPC: Book3S HV P9: Stop handling hcalls in real-mode in the P9 path
From: Nicholas Piggin @ 2021-03-23 9:16 UTC (permalink / raw)
To: Alexey Kardashevskiy, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <6901d698-f3d8-024b-3aa1-47b157bbd57d@ozlabs.ru>
Excerpts from Alexey Kardashevskiy's message of March 23, 2021 7:02 pm:
>
>
> On 23/03/2021 12:02, Nicholas Piggin wrote:
>> In the interest of minimising the amount of code that is run in
>> "real-mode", don't handle hcalls in real mode in the P9 path.
>>
>> POWER8 and earlier are much more expensive to exit from HV real mode
>> and switch to host mode, because on those processors HV interrupts get
>> to the hypervisor with the MMU off, and the other threads in the core
>> need to be pulled out of the guest, and SLBs all need to be saved,
>> ERATs invalidated, and host SLB reloaded before the MMU is re-enabled
>> in host mode. Hash guests also require a lot of hcalls to run. The
>> XICS interrupt controller requires hcalls to run.
>>
>> By contrast, POWER9 has independent thread switching, and in radix mode
>> the hypervisor is already in a host virtual memory mode when the HV
>> interrupt is taken. Radix + xive guests don't need hcalls to handle
>> interrupts or manage translations.
>>
>> So it's much less important to handle hcalls in real mode in P9.
>>
>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>> ---
>> arch/powerpc/include/asm/kvm_ppc.h | 5 ++
>> arch/powerpc/kvm/book3s_hv.c | 57 ++++++++++++++++----
>> arch/powerpc/kvm/book3s_hv_rmhandlers.S | 5 ++
>> arch/powerpc/kvm/book3s_xive.c | 70 +++++++++++++++++++++++++
>> 4 files changed, 127 insertions(+), 10 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
>> index 73b1ca5a6471..db6646c2ade2 100644
>> --- a/arch/powerpc/include/asm/kvm_ppc.h
>> +++ b/arch/powerpc/include/asm/kvm_ppc.h
>> @@ -607,6 +607,7 @@ extern void kvmppc_free_pimap(struct kvm *kvm);
>> extern int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall);
>> extern void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu);
>> extern int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd);
>> +extern int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req);
>> extern u64 kvmppc_xics_get_icp(struct kvm_vcpu *vcpu);
>> extern int kvmppc_xics_set_icp(struct kvm_vcpu *vcpu, u64 icpval);
>> extern int kvmppc_xics_connect_vcpu(struct kvm_device *dev,
>> @@ -639,6 +640,8 @@ static inline int kvmppc_xics_enabled(struct kvm_vcpu *vcpu)
>> static inline void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu) { }
>> static inline int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd)
>> { return 0; }
>> +static inline int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req)
>> + { return 0; }
>> #endif
>>
>> #ifdef CONFIG_KVM_XIVE
>> @@ -673,6 +676,7 @@ extern int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq,
>> int level, bool line_status);
>> extern void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu);
>> extern void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu);
>> +extern void kvmppc_xive_cede_vcpu(struct kvm_vcpu *vcpu);
>>
>> static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
>> {
>> @@ -714,6 +718,7 @@ static inline int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 ir
>> int level, bool line_status) { return -ENODEV; }
>> static inline void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu) { }
>> static inline void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu) { }
>> +static inline void kvmppc_xive_cede_vcpu(struct kvm_vcpu *vcpu) { }
>>
>> static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
>> { return 0; }
>> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
>> index fa7614c37e08..17739aaee3d8 100644
>> --- a/arch/powerpc/kvm/book3s_hv.c
>> +++ b/arch/powerpc/kvm/book3s_hv.c
>> @@ -1142,12 +1142,13 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
>> }
>>
>> /*
>> - * Handle H_CEDE in the nested virtualization case where we haven't
>> - * called the real-mode hcall handlers in book3s_hv_rmhandlers.S.
>> + * Handle H_CEDE in the P9 path where we don't call the real-mode hcall
>> + * handlers in book3s_hv_rmhandlers.S.
>> + *
>> * This has to be done early, not in kvmppc_pseries_do_hcall(), so
>> * that the cede logic in kvmppc_run_single_vcpu() works properly.
>> */
>> -static void kvmppc_nested_cede(struct kvm_vcpu *vcpu)
>> +static void kvmppc_cede(struct kvm_vcpu *vcpu)
>> {
>> vcpu->arch.shregs.msr |= MSR_EE;
>> vcpu->arch.ceded = 1;
>> @@ -1403,9 +1404,15 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu,
>> /* hcall - punt to userspace */
>> int i;
>>
>> - /* hypercall with MSR_PR has already been handled in rmode,
>> - * and never reaches here.
>> - */
>> + if (unlikely(vcpu->arch.shregs.msr & MSR_PR)) {
>> + /*
>> + * Guest userspace executed sc 1, reflect it back as a
>> + * privileged program check interrupt.
>> + */
>> + kvmppc_core_queue_program(vcpu, SRR1_PROGPRIV);
>> + r = RESUME_GUEST;
>> + break;
>> + }
>>
>> run->papr_hcall.nr = kvmppc_get_gpr(vcpu, 3);
>> for (i = 0; i < 9; ++i)
>> @@ -3663,6 +3670,12 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit,
>> return trap;
>> }
>>
>> +static inline bool hcall_is_xics(unsigned long req)
>> +{
>> + return (req == H_EOI || req == H_CPPR || req == H_IPI ||
>> + req == H_IPOLL || req == H_XIRR || req == H_XIRR_X);
>
> Do not need braces :)
>
>
>> +}
>> +
>> /*
>> * Virtual-mode guest entry for POWER9 and later when the host and
>> * guest are both using the radix MMU. The LPIDR has already been set.
>> @@ -3774,15 +3787,36 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
>> /* H_CEDE has to be handled now, not later */
>> if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
>> kvmppc_get_gpr(vcpu, 3) == H_CEDE) {
>> - kvmppc_nested_cede(vcpu);
>> + kvmppc_cede(vcpu);
>> kvmppc_set_gpr(vcpu, 3, 0);
>> trap = 0;
>> }
>> } else {
>> kvmppc_xive_push_vcpu(vcpu);
>> trap = kvmhv_load_hv_regs_and_go(vcpu, time_limit, lpcr);
>> + if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
>> + !(vcpu->arch.shregs.msr & MSR_PR)) {
>> + unsigned long req = kvmppc_get_gpr(vcpu, 3);
>> +
>> + /* H_CEDE has to be handled now, not later */
>> + if (req == H_CEDE) {
>> + kvmppc_cede(vcpu);
>> + kvmppc_xive_cede_vcpu(vcpu); /* may un-cede */
>> + kvmppc_set_gpr(vcpu, 3, 0);
>> + trap = 0;
>> +
>> + /* XICS hcalls must be handled before xive is pulled */
>> + } else if (hcall_is_xics(req)) {
>> + int ret;
>> +
>> + ret = kvmppc_xive_xics_hcall(vcpu, req);
>> + if (ret != H_TOO_HARD) {
>> + kvmppc_set_gpr(vcpu, 3, ret);
>> + trap = 0;
>> + }
>> + }
>> + }
>> kvmppc_xive_pull_vcpu(vcpu);
>> -
>> }
>>
>> vcpu->arch.slb_max = 0;
>> @@ -4442,8 +4476,11 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu)
>> else
>> r = kvmppc_run_vcpu(vcpu);
>>
>> - if (run->exit_reason == KVM_EXIT_PAPR_HCALL &&
>> - !(vcpu->arch.shregs.msr & MSR_PR)) {
>> + if (run->exit_reason == KVM_EXIT_PAPR_HCALL) {
>> + if (WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_PR)) {
>> + r = RESUME_GUEST;
>> + continue;
>> + }
>> trace_kvm_hcall_enter(vcpu);
>> r = kvmppc_pseries_do_hcall(vcpu);
>> trace_kvm_hcall_exit(vcpu, r);
>> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
>> index c11597f815e4..2d0d14ed1d92 100644
>> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
>> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
>> @@ -1397,9 +1397,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
>> mr r4,r9
>> bge fast_guest_return
>> 2:
>> + /* If we came in through the P9 short path, no real mode hcalls */
>> + lwz r0, STACK_SLOT_SHORT_PATH(r1)
>> + cmpwi r0, 0
>> + bne no_try_real
>
>
> btw is mmu on at this point? or it gets enabled by rfid at the end of
> guest_exit_short_path?
Hash guest it's off. Radix guest it can be on or off depending on the
interrupt type and MSR and LPCR[AIL] values.
Thanks,
Nick
^ permalink raw reply
* Re: [PATCH v4 22/46] KVM: PPC: Book3S HV P9: Stop handling hcalls in real-mode in the P9 path
From: Alexey Kardashevskiy @ 2021-03-23 9:24 UTC (permalink / raw)
To: Nicholas Piggin, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <1616490842.v369xyk7do.astroid@bobo.none>
On 23/03/2021 20:16, Nicholas Piggin wrote:
> Excerpts from Alexey Kardashevskiy's message of March 23, 2021 7:02 pm:
>>
>>
>> On 23/03/2021 12:02, Nicholas Piggin wrote:
>>> In the interest of minimising the amount of code that is run in
>>> "real-mode", don't handle hcalls in real mode in the P9 path.
>>>
>>> POWER8 and earlier are much more expensive to exit from HV real mode
>>> and switch to host mode, because on those processors HV interrupts get
>>> to the hypervisor with the MMU off, and the other threads in the core
>>> need to be pulled out of the guest, and SLBs all need to be saved,
>>> ERATs invalidated, and host SLB reloaded before the MMU is re-enabled
>>> in host mode. Hash guests also require a lot of hcalls to run. The
>>> XICS interrupt controller requires hcalls to run.
>>>
>>> By contrast, POWER9 has independent thread switching, and in radix mode
>>> the hypervisor is already in a host virtual memory mode when the HV
>>> interrupt is taken. Radix + xive guests don't need hcalls to handle
>>> interrupts or manage translations.
>>>
>>> So it's much less important to handle hcalls in real mode in P9.
>>>
>>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>>> ---
>>> arch/powerpc/include/asm/kvm_ppc.h | 5 ++
>>> arch/powerpc/kvm/book3s_hv.c | 57 ++++++++++++++++----
>>> arch/powerpc/kvm/book3s_hv_rmhandlers.S | 5 ++
>>> arch/powerpc/kvm/book3s_xive.c | 70 +++++++++++++++++++++++++
>>> 4 files changed, 127 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
>>> index 73b1ca5a6471..db6646c2ade2 100644
>>> --- a/arch/powerpc/include/asm/kvm_ppc.h
>>> +++ b/arch/powerpc/include/asm/kvm_ppc.h
>>> @@ -607,6 +607,7 @@ extern void kvmppc_free_pimap(struct kvm *kvm);
>>> extern int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall);
>>> extern void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu);
>>> extern int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd);
>>> +extern int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req);
>>> extern u64 kvmppc_xics_get_icp(struct kvm_vcpu *vcpu);
>>> extern int kvmppc_xics_set_icp(struct kvm_vcpu *vcpu, u64 icpval);
>>> extern int kvmppc_xics_connect_vcpu(struct kvm_device *dev,
>>> @@ -639,6 +640,8 @@ static inline int kvmppc_xics_enabled(struct kvm_vcpu *vcpu)
>>> static inline void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu) { }
>>> static inline int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd)
>>> { return 0; }
>>> +static inline int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req)
>>> + { return 0; }
>>> #endif
>>>
>>> #ifdef CONFIG_KVM_XIVE
>>> @@ -673,6 +676,7 @@ extern int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq,
>>> int level, bool line_status);
>>> extern void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu);
>>> extern void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu);
>>> +extern void kvmppc_xive_cede_vcpu(struct kvm_vcpu *vcpu);
>>>
>>> static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
>>> {
>>> @@ -714,6 +718,7 @@ static inline int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 ir
>>> int level, bool line_status) { return -ENODEV; }
>>> static inline void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu) { }
>>> static inline void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu) { }
>>> +static inline void kvmppc_xive_cede_vcpu(struct kvm_vcpu *vcpu) { }
>>>
>>> static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
>>> { return 0; }
>>> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
>>> index fa7614c37e08..17739aaee3d8 100644
>>> --- a/arch/powerpc/kvm/book3s_hv.c
>>> +++ b/arch/powerpc/kvm/book3s_hv.c
>>> @@ -1142,12 +1142,13 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
>>> }
>>>
>>> /*
>>> - * Handle H_CEDE in the nested virtualization case where we haven't
>>> - * called the real-mode hcall handlers in book3s_hv_rmhandlers.S.
>>> + * Handle H_CEDE in the P9 path where we don't call the real-mode hcall
>>> + * handlers in book3s_hv_rmhandlers.S.
>>> + *
>>> * This has to be done early, not in kvmppc_pseries_do_hcall(), so
>>> * that the cede logic in kvmppc_run_single_vcpu() works properly.
>>> */
>>> -static void kvmppc_nested_cede(struct kvm_vcpu *vcpu)
>>> +static void kvmppc_cede(struct kvm_vcpu *vcpu)
>>> {
>>> vcpu->arch.shregs.msr |= MSR_EE;
>>> vcpu->arch.ceded = 1;
>>> @@ -1403,9 +1404,15 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu,
>>> /* hcall - punt to userspace */
>>> int i;
>>>
>>> - /* hypercall with MSR_PR has already been handled in rmode,
>>> - * and never reaches here.
>>> - */
>>> + if (unlikely(vcpu->arch.shregs.msr & MSR_PR)) {
>>> + /*
>>> + * Guest userspace executed sc 1, reflect it back as a
>>> + * privileged program check interrupt.
>>> + */
>>> + kvmppc_core_queue_program(vcpu, SRR1_PROGPRIV);
>>> + r = RESUME_GUEST;
>>> + break;
>>> + }
>>>
>>> run->papr_hcall.nr = kvmppc_get_gpr(vcpu, 3);
>>> for (i = 0; i < 9; ++i)
>>> @@ -3663,6 +3670,12 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit,
>>> return trap;
>>> }
>>>
>>> +static inline bool hcall_is_xics(unsigned long req)
>>> +{
>>> + return (req == H_EOI || req == H_CPPR || req == H_IPI ||
>>> + req == H_IPOLL || req == H_XIRR || req == H_XIRR_X);
>>
>> Do not need braces :)
>>
>>
>>> +}
>>> +
>>> /*
>>> * Virtual-mode guest entry for POWER9 and later when the host and
>>> * guest are both using the radix MMU. The LPIDR has already been set.
>>> @@ -3774,15 +3787,36 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
>>> /* H_CEDE has to be handled now, not later */
>>> if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
>>> kvmppc_get_gpr(vcpu, 3) == H_CEDE) {
>>> - kvmppc_nested_cede(vcpu);
>>> + kvmppc_cede(vcpu);
>>> kvmppc_set_gpr(vcpu, 3, 0);
>>> trap = 0;
>>> }
>>> } else {
>>> kvmppc_xive_push_vcpu(vcpu);
>>> trap = kvmhv_load_hv_regs_and_go(vcpu, time_limit, lpcr);
>>> + if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
>>> + !(vcpu->arch.shregs.msr & MSR_PR)) {
>>> + unsigned long req = kvmppc_get_gpr(vcpu, 3);
>>> +
>>> + /* H_CEDE has to be handled now, not later */
>>> + if (req == H_CEDE) {
>>> + kvmppc_cede(vcpu);
>>> + kvmppc_xive_cede_vcpu(vcpu); /* may un-cede */
>>> + kvmppc_set_gpr(vcpu, 3, 0);
>>> + trap = 0;
>>> +
>>> + /* XICS hcalls must be handled before xive is pulled */
>>> + } else if (hcall_is_xics(req)) {
>>> + int ret;
>>> +
>>> + ret = kvmppc_xive_xics_hcall(vcpu, req);
>>> + if (ret != H_TOO_HARD) {
>>> + kvmppc_set_gpr(vcpu, 3, ret);
>>> + trap = 0;
>>> + }
>>> + }
>>> + }
>>> kvmppc_xive_pull_vcpu(vcpu);
>>> -
>>> }
>>>
>>> vcpu->arch.slb_max = 0;
>>> @@ -4442,8 +4476,11 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu)
>>> else
>>> r = kvmppc_run_vcpu(vcpu);
>>>
>>> - if (run->exit_reason == KVM_EXIT_PAPR_HCALL &&
>>> - !(vcpu->arch.shregs.msr & MSR_PR)) {
>>> + if (run->exit_reason == KVM_EXIT_PAPR_HCALL) {
>>> + if (WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_PR)) {
>>> + r = RESUME_GUEST;
>>> + continue;
>>> + }
>>> trace_kvm_hcall_enter(vcpu);
>>> r = kvmppc_pseries_do_hcall(vcpu);
>>> trace_kvm_hcall_exit(vcpu, r);
>>> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
>>> index c11597f815e4..2d0d14ed1d92 100644
>>> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
>>> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
>>> @@ -1397,9 +1397,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
>>> mr r4,r9
>>> bge fast_guest_return
>>> 2:
>>> + /* If we came in through the P9 short path, no real mode hcalls */
>>> + lwz r0, STACK_SLOT_SHORT_PATH(r1)
>>> + cmpwi r0, 0
>>> + bne no_try_real
>>
>>
>> btw is mmu on at this point? or it gets enabled by rfid at the end of
>> guest_exit_short_path?
>
> Hash guest it's off. Radix guest it can be on or off depending on the
> interrupt type and MSR and LPCR[AIL] values.
What I meant was - what do we expect here on p9? mmu on? ^w^w^w^w^w^w^w^w^w
I just realized - it is radix so there is no problem with vmalloc
addresses in real mode as these do not use top 2 bits as on hash and the
exact mmu state is less important here. Cheers.
>
> Thanks,
> Nick
>
--
Alexey
^ permalink raw reply
* Re: [PATCH 3/4] powerpc/rust: Add target.json for ppc64le
From: Miguel Ojeda @ 2021-03-23 9:28 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, linux-kernel, rust-for-linux
In-Reply-To: <20210323032624.1039422-4-mpe@ellerman.id.au>
On Tue, Mar 23, 2021 at 4:27 AM Michael Ellerman <mpe@ellerman.id.au> wrote:
>
> ppc64le only for now. We'll eventually need to come up with some way to
> change the target.json that's used based on more than just $(ARCH).
Indeed, it is one reason I didn't tackle e.g. x86 32-bit, because I
wanted to figure out how to do the whole `target.json` cleanly (i.e.
likely have a script generate them on the fly), so I thought it was
better to wait post-RFC.
Cheers,
Miguel
^ permalink raw reply
* Re: [PATCH next v1 2/3] printk: remove safe buffers
From: Petr Mladek @ 2021-03-23 9:46 UTC (permalink / raw)
To: John Ogness
Cc: Rafael Aquini, Alexey Kardashevskiy, Paul Mackerras, Tiezhu Yang,
Peter Zijlstra, Yue Hu, Jordan Niethe, Kees Cook,
Paul E. McKenney, Alistair Popple, Guilherme G. Piccoli,
Nicholas Piggin, Steven Rostedt, Thomas Gleixner, kexec,
linux-kernel, Sergey Senozhatsky, Eric Biederman, Andrew Morton,
linuxppc-dev, Cédric Le Goater
In-Reply-To: <87ft0mg8a0.fsf@jogness.linutronix.de>
On Mon 2021-03-22 22:58:47, John Ogness wrote:
> On 2021-03-22, Petr Mladek <pmladek@suse.com> wrote:
> > On Mon 2021-03-22 12:16:15, John Ogness wrote:
> >> On 2021-03-21, Sergey Senozhatsky <senozhatsky@chromium.org> wrote:
> >> >> @@ -369,7 +70,10 @@ __printf(1, 0) int vprintk_func(const char *fmt, va_list args)
> >> >> * Use the main logbuf even in NMI. But avoid calling console
> >> >> * drivers that might have their own locks.
> >> >> */
> >> >> - if ((this_cpu_read(printk_context) & PRINTK_NMI_DIRECT_CONTEXT_MASK)) {
> >> >> + if (this_cpu_read(printk_context) &
> >> >> + (PRINTK_NMI_DIRECT_CONTEXT_MASK |
> >> >> + PRINTK_NMI_CONTEXT_MASK |
> >> >> + PRINTK_SAFE_CONTEXT_MASK)) {
> >> >
> >> But I suppose I could switch
> >> the 1 printk_nmi_direct_enter() user to printk_nmi_enter() so that
> >> PRINTK_NMI_DIRECT_CONTEXT_MASK can be removed now. I would do this in a
> >> 4th patch of the series.
> >
> > Yes, please unify the PRINTK_NMI_CONTEXT. One is enough.
>
> Agreed. (But I'll go even further. See below.)
>
> > I wonder if it would make sense to go even further at this stage.
> > What is possible?
> >
> > 1. We could get rid of printk_nmi_enter()/exit() and
> > PRINTK_NMI_CONTEXT completely already now. It is enough
> > to check in_nmi() in printk_func().
> >
>
> Agreed. in_nmi() within vprintk_emit() is enough to detect if the
> console code should be skipped:
>
> if (!in_sched && !in_nmi()) {
> ...
> }
Well, we also need to make sure that the irq work is scheduled to
call console later. We should keep this dicision in
printk_func(). I mean to replace the current
if (this_cpu_read(printk_context) &
(PRINTK_NMI_DIRECT_CONTEXT_MASK |
PRINTK_NMI_CONTEXT_MASK |
PRINTK_SAFE_CONTEXT_MASK)) {
with
/*
* Avoid calling console drivers in recursive printk()
* and in NMI context.
*/
if (this_cpu_read(printk_context) || in_nmi() {
That said, I am not sure how this fits your further rework.
I do not want to complicate it too much.
I am just afraid that the discussion about console rework might
take some time. And this would remove some complexity before we
started the more complicated or controversial changes.
> > 2. I thought about unifying printk_safe_enter()/exit() and
> > printk_enter()/exit(). They both count recursion with
> > IRQs disabled, have similar name. But they are used
> > different way.
> >
> > But better might be to rename printk_safe_enter()/exit() to
> > console_enter()/exit() or to printk_deferred_enter()/exit().
> > It would make more clear what it does now. And it might help
> > to better distinguish it from the new printk_enter()/exit().
> >
> > I am not sure if it is worth it.
>
> I am also not sure if it is worth the extra "noise" just to give the
> function a more appropriate name. The plan is to remove it completely
> soon anyway. My vote is to leave the name as it is.
OK, let's keep printk_safe() name. It was just an idea. I wrote it
primary to sort my thoughts.
Best Regards,
Petr
^ permalink raw reply
* Re: [PATCH v4 22/46] KVM: PPC: Book3S HV P9: Stop handling hcalls in real-mode in the P9 path
From: Nicholas Piggin @ 2021-03-23 9:48 UTC (permalink / raw)
To: Alexey Kardashevskiy, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <994fb056-4445-4301-faca-b53394fb6b35@ozlabs.ru>
Excerpts from Alexey Kardashevskiy's message of March 23, 2021 7:24 pm:
>
>
> On 23/03/2021 20:16, Nicholas Piggin wrote:
>> Excerpts from Alexey Kardashevskiy's message of March 23, 2021 7:02 pm:
>>>
>>>
>>> On 23/03/2021 12:02, Nicholas Piggin wrote:
>>>> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
>>>> index c11597f815e4..2d0d14ed1d92 100644
>>>> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
>>>> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
>>>> @@ -1397,9 +1397,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
>>>> mr r4,r9
>>>> bge fast_guest_return
>>>> 2:
>>>> + /* If we came in through the P9 short path, no real mode hcalls */
>>>> + lwz r0, STACK_SLOT_SHORT_PATH(r1)
>>>> + cmpwi r0, 0
>>>> + bne no_try_real
>>>
>>>
>>> btw is mmu on at this point? or it gets enabled by rfid at the end of
>>> guest_exit_short_path?
>>
>> Hash guest it's off. Radix guest it can be on or off depending on the
>> interrupt type and MSR and LPCR[AIL] values.
>
> What I meant was - what do we expect here on p9? mmu on? ^w^w^w^w^w^w^w^w^w
P9 radix can be on or off. If the guest had MSR[IR] or MSR[DR] clear, or
if the guest is running AIL=0 mode, or if this is a machine check,
system reset, or HMI interrupt then the MMU will be off here.
> I just realized - it is radix so there is no problem with vmalloc
> addresses in real mode as these do not use top 2 bits as on hash and the
> exact mmu state is less important here. Cheers.
We still can't use vmalloc addresses in real mode on radix because they
don't translate with the page tables.
Thanks,
Nick
^ permalink raw reply
* Re: [PATCH 0/4] Rust for Linux for ppc64le
From: Miguel Ojeda @ 2021-03-23 10:02 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, linux-kernel, rust-for-linux
In-Reply-To: <20210323032624.1039422-1-mpe@ellerman.id.au>
Hi Michael,
On Tue, Mar 23, 2021 at 4:27 AM Michael Ellerman <mpe@ellerman.id.au> wrote:
>
> Hi all,
>
> Here's a first attempt at getting the kernel Rust support building on powerpc.
Thanks a *lot*! It is great to have more architectures rolling.
> It's powerpc64le only for now, as that's what I can easily test given the
> distros I have installed. Though powerpc and powerpc64 are also Tier 2 platforms
Even if it is just 64-bit, it is very good to have it!
> so in theory should work. Supporting those would require something more
> complicated than just pointing rustc at arch/$(ARCH)/rust/target.json.
Yeah, the arch/$(ARCH)/rust/target.json dance is a placeholder -- I
need to figure out how to do that more cleanly, likely generating them
on the fly.
> This is based on 832575d934a2 from the Rust-for-Linux tree. Anything newer gives
> me errors about symbol name lengths. I figured I'd send this anyway, as it seems
> like those errors are probably not powerpc specific.
Sure, feel free to send things even if they don't work completely.
I will take a look at the symbol name lengths -- I increased that
limit to 512 and added support for 2-byte lengths in the tables, but
perhaps something is missing. If I manage to make it work, I can add
ppc64le to our CI! :-)
> Michael Ellerman (4):
> rust: Export symbols in initialized data section
> rust: Add powerpc64 as a 64-bit target_arch in c_types.rs
> powerpc/rust: Add target.json for ppc64le
> rust: Enable for ppc64le
Regarding the development process: at least until the RFC we are
working with the usual GitHub PR workflow (for several reasons: having
a quick CI setup, getting new Rust developers on-board, having a list
of "issues", cross-reference with the Rust repo, etc.).
I can take patches from the list, of course, but since we are pre-RFC,
do you mind if they get rebased etc. through there?
Thanks again!
Cheers,
Miguel
^ permalink raw reply
* Re: [PATCH v4 28/46] KVM: PPC: Book3S HV P9: Reduce irq_work vs guest decrementer races
From: Alexey Kardashevskiy @ 2021-03-23 10:13 UTC (permalink / raw)
To: Nicholas Piggin, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <20210323010305.1045293-29-npiggin@gmail.com>
On 23/03/2021 12:02, Nicholas Piggin wrote:
> irq_work's use of the DEC SPR is racy with guest<->host switch and guest
> entry which flips the DEC interrupt to guest, which could lose a host
> work interrupt.
>
> This patch closes one race, and attempts to comment another class of
> races.
>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
> arch/powerpc/kvm/book3s_hv.c | 15 ++++++++++++++-
> 1 file changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index 1f38a0abc611..989a1ff5ad11 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -3745,6 +3745,18 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
> if (!(vcpu->arch.ctrl & 1))
> mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
>
> + /*
> + * When setting DEC, we must always deal with irq_work_raise via NMI vs
> + * setting DEC. The problem occurs right as we switch into guest mode
> + * if a NMI hits and sets pending work and sets DEC, then that will
> + * apply to the guest and not bring us back to the host.
> + *
> + * irq_work_raise could check a flag (or possibly LPCR[HDICE] for
> + * example) and set HDEC to 1? That wouldn't solve the nested hv
> + * case which needs to abort the hcall or zero the time limit.
> + *
> + * XXX: Another day's problem.
> + */
> mtspr(SPRN_DEC, vcpu->arch.dec_expires - tb);
>
> if (kvmhv_on_pseries()) {
> @@ -3879,7 +3891,8 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
> vc->entry_exit_map = 0x101;
> vc->in_guest = 0;
>
> - mtspr(SPRN_DEC, local_paca->kvm_hstate.dec_expires - tb);
> + set_dec_or_work(local_paca->kvm_hstate.dec_expires - tb);
set_dec_or_work() will write local_paca->kvm_hstate.dec_expires - tb - 1
to SPRN_DEC which is not exactly the same, is this still alright?
I asked in v3 but it is probably lost :)
> +
> mtspr(SPRN_SPRG_VDSO_WRITE, local_paca->sprg_vdso);
>
> kvmhv_load_host_pmu();
>
--
Alexey
^ permalink raw reply
* [PATCH] sound:ppc: fix spelling typo of values
From: caizhichao @ 2021-03-23 8:55 UTC (permalink / raw)
To: geoff, perex, tiwai
Cc: alsa-devel, caizhichao, linux-kernel, paulus, linuxppc-dev
From: caizhichao <caizhichao@yulong.com>
vaules -> values
Signed-off-by: caizhichao <caizhichao@yulong.com>
---
sound/ppc/snd_ps3_reg.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/ppc/snd_ps3_reg.h b/sound/ppc/snd_ps3_reg.h
index 566a318..e2212b7 100644
--- a/sound/ppc/snd_ps3_reg.h
+++ b/sound/ppc/snd_ps3_reg.h
@@ -308,7 +308,7 @@
each interrupt in this register.
Writing 1b to a field containing 1b clears field and de-asserts interrupt.
Writing 0b to a field has no effect.
-Field vaules are the following:
+Field values are the following:
0 - Interrupt hasn't occurred.
1 - Interrupt has occurred.
--
1.9.1
^ permalink raw reply related
* Re: [PATCH v4 28/46] KVM: PPC: Book3S HV P9: Reduce irq_work vs guest decrementer races
From: Nicholas Piggin @ 2021-03-23 10:36 UTC (permalink / raw)
To: Alexey Kardashevskiy, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <3ca0e504-70df-2a25-12af-a1addac842b6@ozlabs.ru>
Excerpts from Alexey Kardashevskiy's message of March 23, 2021 8:13 pm:
>
>
> On 23/03/2021 12:02, Nicholas Piggin wrote:
>> irq_work's use of the DEC SPR is racy with guest<->host switch and guest
>> entry which flips the DEC interrupt to guest, which could lose a host
>> work interrupt.
>>
>> This patch closes one race, and attempts to comment another class of
>> races.
>>
>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>> ---
>> arch/powerpc/kvm/book3s_hv.c | 15 ++++++++++++++-
>> 1 file changed, 14 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
>> index 1f38a0abc611..989a1ff5ad11 100644
>> --- a/arch/powerpc/kvm/book3s_hv.c
>> +++ b/arch/powerpc/kvm/book3s_hv.c
>> @@ -3745,6 +3745,18 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
>> if (!(vcpu->arch.ctrl & 1))
>> mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
>>
>> + /*
>> + * When setting DEC, we must always deal with irq_work_raise via NMI vs
>> + * setting DEC. The problem occurs right as we switch into guest mode
>> + * if a NMI hits and sets pending work and sets DEC, then that will
>> + * apply to the guest and not bring us back to the host.
>> + *
>> + * irq_work_raise could check a flag (or possibly LPCR[HDICE] for
>> + * example) and set HDEC to 1? That wouldn't solve the nested hv
>> + * case which needs to abort the hcall or zero the time limit.
>> + *
>> + * XXX: Another day's problem.
>> + */
>> mtspr(SPRN_DEC, vcpu->arch.dec_expires - tb);
>>
>> if (kvmhv_on_pseries()) {
>> @@ -3879,7 +3891,8 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
>> vc->entry_exit_map = 0x101;
>> vc->in_guest = 0;
>>
>> - mtspr(SPRN_DEC, local_paca->kvm_hstate.dec_expires - tb);
>> + set_dec_or_work(local_paca->kvm_hstate.dec_expires - tb);
>
>
> set_dec_or_work() will write local_paca->kvm_hstate.dec_expires - tb - 1
> to SPRN_DEC which is not exactly the same, is this still alright?
>
> I asked in v3 but it is probably lost :)
Oh I did see that then forgot.
It will write dec_expires - tb, then it will write 1 if it found irq_work
was pending.
The change is intentional to fixes one of the lost irq_work races.
Thanks,
Nick
^ permalink raw reply
* Re: [PATCH next v1 2/3] printk: remove safe buffers
From: Petr Mladek @ 2021-03-23 10:47 UTC (permalink / raw)
To: John Ogness
Cc: Sergey Senozhatsky, Peter Zijlstra, Paul Mackerras, Tiezhu Yang,
Rafael Aquini, Alexey Kardashevskiy, Yue Hu, Jordan Niethe,
Kees Cook, Paul E. McKenney, Alistair Popple,
Guilherme G. Piccoli, Nicholas Piggin, Steven Rostedt,
Thomas Gleixner, kexec, linux-kernel, Sergey Senozhatsky,
Eric Biederman, Andrew Morton, linuxppc-dev,
Cédric Le Goater
In-Reply-To: <20210316233326.10778-3-john.ogness@linutronix.de>
On Wed 2021-03-17 00:33:25, John Ogness wrote:
> With @logbuf_lock removed, the high level printk functions for
> storing messages are lockless. Messages can be stored from any
> context, so there is no need for the NMI and safe buffers anymore.
> Remove the NMI and safe buffers.
>
> Although the safe buffers are removed, the NMI and safe context
> tracking is still in place. In these contexts, store the message
> immediately but still use irq_work to defer the console printing.
>
> Since printk recursion tracking is in place, safe context tracking
> for most of printk is not needed. Remove it. Only safe context
> tracking relating to the console lock is left in place. This is
> because the console lock is needed for the actual printing.
I have two more questions after actually checking the entire patch.
See below.
> --- a/kernel/printk/printk.c
> +++ b/kernel/printk/printk.c
> @@ -1084,7 +1069,6 @@ void __init setup_log_buf(int early)
> struct printk_record r;
> size_t new_descs_size;
> size_t new_infos_size;
> - unsigned long flags;
> char *new_log_buf;
> unsigned int free;
> u64 seq;
> @@ -1142,8 +1126,6 @@ void __init setup_log_buf(int early)
> new_descs, ilog2(new_descs_count),
> new_infos);
>
> - printk_safe_enter_irqsave(flags);
> -
> log_buf_len = new_log_buf_len;
> log_buf = new_log_buf;
> new_log_buf_len = 0;
> @@ -1159,8 +1141,6 @@ void __init setup_log_buf(int early)
> */
> prb = &printk_rb_dynamic;
>
> - printk_safe_exit_irqrestore(flags);
This will allow to add new messages from the IRQ context when we
are copying them to the new buffer. They might get lost in
the small race window.
Also the messages from NMI might get lost because they are not
longer stored in the per-CPU buffer.
A possible solution might be to do something like this:
prb_for_each_record(0, &printk_rb_static, seq, &r)
free -= add_to_rb(&printk_rb_dynamic, &r);
prb = &printk_rb_dynamic;
/*
* Copy the remaining messages that might have appeared
* from IRQ or NMI context after we ended copying and
* before we switched the buffers. They must be finalized
* because only one CPU is up at this stage.
*/
prb_for_each_record(seq, &printk_rb_static, seq, &r)
free -= add_to_rb(&printk_rb_dynamic, &r);
> -
> if (seq != prb_next_seq(&printk_rb_static)) {
> pr_err("dropped %llu messages\n",
> prb_next_seq(&printk_rb_static) - seq);
> @@ -2666,7 +2631,6 @@ void console_unlock(void)
> size_t ext_len = 0;
> size_t len;
>
> - printk_safe_enter_irqsave(flags);
> skip:
> if (!prb_read_valid(prb, console_seq, &r))
> break;
> @@ -2711,6 +2675,8 @@ void console_unlock(void)
> printk_time);
> console_seq++;
>
> + printk_safe_enter_irqsave(flags);
What is the purpose of the printk_safe context here, please?
I guess that you wanted to prevent calling console drivers
recursively. But it is already serialized by console_lock().
IMHO, the only risk is when manipulating console_sem->lock
or console_owner_lock. But they are already guarded by
printk_safe context, for example, in console_lock() or
console_lock_spinning_enable().
Do I miss something, please?
> +
> /*
> * While actively printing out messages, if another printk()
> * were to occur on another CPU, it may wait for this one to
> @@ -2745,8 +2711,6 @@ void console_unlock(void)
> * flush, no worries.
> */
> retry = prb_read_valid(prb, console_seq, NULL);
> - printk_safe_exit_irqrestore(flags);
> -
> if (retry && console_trylock())
> goto again;
> }
Heh, all these patches feels like stripping printk of an armour. I hope
that we trained it enough to be flexible and avoid any damage.
Best Regards,
Petr
^ permalink raw reply
* Re: [PATCH v4 28/46] KVM: PPC: Book3S HV P9: Reduce irq_work vs guest decrementer races
From: Nicholas Piggin @ 2021-03-23 11:15 UTC (permalink / raw)
To: Alexey Kardashevskiy, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <1616495617.6070udmp89.astroid@bobo.none>
Excerpts from Nicholas Piggin's message of March 23, 2021 8:36 pm:
> Excerpts from Alexey Kardashevskiy's message of March 23, 2021 8:13 pm:
>>
>>
>> On 23/03/2021 12:02, Nicholas Piggin wrote:
>>> irq_work's use of the DEC SPR is racy with guest<->host switch and guest
>>> entry which flips the DEC interrupt to guest, which could lose a host
>>> work interrupt.
>>>
>>> This patch closes one race, and attempts to comment another class of
>>> races.
>>>
>>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>>> ---
>>> arch/powerpc/kvm/book3s_hv.c | 15 ++++++++++++++-
>>> 1 file changed, 14 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
>>> index 1f38a0abc611..989a1ff5ad11 100644
>>> --- a/arch/powerpc/kvm/book3s_hv.c
>>> +++ b/arch/powerpc/kvm/book3s_hv.c
>>> @@ -3745,6 +3745,18 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
>>> if (!(vcpu->arch.ctrl & 1))
>>> mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
>>>
>>> + /*
>>> + * When setting DEC, we must always deal with irq_work_raise via NMI vs
>>> + * setting DEC. The problem occurs right as we switch into guest mode
>>> + * if a NMI hits and sets pending work and sets DEC, then that will
>>> + * apply to the guest and not bring us back to the host.
>>> + *
>>> + * irq_work_raise could check a flag (or possibly LPCR[HDICE] for
>>> + * example) and set HDEC to 1? That wouldn't solve the nested hv
>>> + * case which needs to abort the hcall or zero the time limit.
>>> + *
>>> + * XXX: Another day's problem.
>>> + */
>>> mtspr(SPRN_DEC, vcpu->arch.dec_expires - tb);
>>>
>>> if (kvmhv_on_pseries()) {
>>> @@ -3879,7 +3891,8 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
>>> vc->entry_exit_map = 0x101;
>>> vc->in_guest = 0;
>>>
>>> - mtspr(SPRN_DEC, local_paca->kvm_hstate.dec_expires - tb);
>>> + set_dec_or_work(local_paca->kvm_hstate.dec_expires - tb);
>>
>>
>> set_dec_or_work() will write local_paca->kvm_hstate.dec_expires - tb - 1
>> to SPRN_DEC which is not exactly the same, is this still alright?
>>
>> I asked in v3 but it is probably lost :)
>
> Oh I did see that then forgot.
>
> It will write dec_expires - tb, then it will write 1 if it found irq_work
> was pending.
Ah you were actually asking about set_dec writing val - 1. I totally
missed that.
Yes that was an unintentional change. This is the way timer.c code works
with respect to the decrementers_next_tb value, so it's probably better
to make them so it seems like it should be okay (and better to bring the
KVM code up to match timer code rather than be different or the other
way around). The difference should be noted in the changelog though.
Thanks,
Nick
^ permalink raw reply
* Re: [PATCH 0/2] handle premature return from H_JOIN in pseries mobility code
From: Michael Ellerman @ 2021-03-23 12:02 UTC (permalink / raw)
To: linuxppc-dev, Nathan Lynch; +Cc: tyreld, brking, npiggin
In-Reply-To: <20210315080045.460331-1-nathanl@linux.ibm.com>
On Mon, 15 Mar 2021 03:00:43 -0500, Nathan Lynch wrote:
> pseries VMs in shared processor mode are susceptible to failed
> migrations becasue stray H_PRODs from the paravirt spinlock
> implementation can bump threads out of joining state before the
> suspend has occurred. Fix this by adding a small amount of shared
> state and ordering accesses to it with respect to H_PROD and H_JOIN.
>
> Nathan Lynch (2):
> powerpc/pseries/mobility: use struct for shared state
> powerpc/pseries/mobility: handle premature return from H_JOIN
>
> [...]
Applied to powerpc/fixes.
[1/2] powerpc/pseries/mobility: use struct for shared state
https://git.kernel.org/powerpc/c/e834df6cfc71d8e5ce2c27a0184145ea125c3f0f
[2/2] powerpc/pseries/mobility: handle premature return from H_JOIN
https://git.kernel.org/powerpc/c/274cb1ca2e7ce02cab56f5f4c61a74aeb566f931
cheers
^ permalink raw reply
* Re: [PATCH 0/4] Rust for Linux for ppc64le
From: Michael Ellerman @ 2021-03-23 12:15 UTC (permalink / raw)
To: Miguel Ojeda; +Cc: linuxppc-dev, linux-kernel, rust-for-linux
In-Reply-To: <CANiq72n-tMww2U+eQ=iHOh5u1JQgjM0b1E3XQ9jpWMfpdQ5+=g@mail.gmail.com>
Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> writes:
> Hi Michael,
>
> On Tue, Mar 23, 2021 at 4:27 AM Michael Ellerman <mpe@ellerman.id.au> wrote:
>>
>> Hi all,
>>
>> Here's a first attempt at getting the kernel Rust support building on powerpc.
>
> Thanks a *lot*! It is great to have more architectures rolling.
No worries.
>> It's powerpc64le only for now, as that's what I can easily test given the
>> distros I have installed. Though powerpc and powerpc64 are also Tier 2 platforms
>
> Even if it is just 64-bit, it is very good to have it!
>
>> so in theory should work. Supporting those would require something more
>> complicated than just pointing rustc at arch/$(ARCH)/rust/target.json.
>
> Yeah, the arch/$(ARCH)/rust/target.json dance is a placeholder -- I
> need to figure out how to do that more cleanly, likely generating them
> on the fly.
Yeah that's a good idea. That way they can be made to exactly match the
kernel configuration.
>> This is based on 832575d934a2 from the Rust-for-Linux tree. Anything newer gives
>> me errors about symbol name lengths. I figured I'd send this anyway, as it seems
>> like those errors are probably not powerpc specific.
>
> Sure, feel free to send things even if they don't work completely.
>
> I will take a look at the symbol name lengths -- I increased that
> limit to 512 and added support for 2-byte lengths in the tables, but
> perhaps something is missing. If I manage to make it work, I can add
> ppc64le to our CI! :-)
It would be nice to be in the CI. I was building natively so I haven't
tried cross compiling yet (which we'll need for CI).
>> Michael Ellerman (4):
>> rust: Export symbols in initialized data section
>> rust: Add powerpc64 as a 64-bit target_arch in c_types.rs
>> powerpc/rust: Add target.json for ppc64le
>> rust: Enable for ppc64le
>
> Regarding the development process: at least until the RFC we are
> working with the usual GitHub PR workflow (for several reasons: having
> a quick CI setup, getting new Rust developers on-board, having a list
> of "issues", cross-reference with the Rust repo, etc.).
>
> I can take patches from the list, of course, but since we are pre-RFC,
> do you mind if they get rebased etc. through there?
No I don't mind at all. I just sent patches so other ppc folks could see
what I had, and it's kind of the process I'm used to.
I can send a pull request if that's easiest.
cheers
^ permalink raw reply
* [PATCH] soc/fsl: qbman: fix conflicting alignment attributes
From: Arnd Bergmann @ 2021-03-23 13:15 UTC (permalink / raw)
To: Li Yang, Roy Pledge, Claudiu Manoil, Scott Wood
Cc: Arnd Bergmann, linuxppc-dev, Sebastian Andrzej Siewior,
YueHaibing, linux-kernel, soc, Jakub Kicinski, Lee Jones,
linux-arm-kernel
From: Arnd Bergmann <arnd@arndb.de>
When building with W=1, gcc points out that the __packed attribute
on struct qm_eqcr_entry conflicts with the 8-byte alignment
attribute on struct qm_fd inside it:
drivers/soc/fsl/qbman/qman.c:189:1: error: alignment 1 of 'struct qm_eqcr_entry' is less than 8 [-Werror=packed-not-aligned]
I assume that the alignment attribute is the correct one, and
that qm_eqcr_entry cannot actually be unaligned in memory,
so add the same alignment on the outer struct.
Fixes: c535e923bb97 ("soc/fsl: Introduce DPAA 1.x QMan device driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/soc/fsl/qbman/qman.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/soc/fsl/qbman/qman.c b/drivers/soc/fsl/qbman/qman.c
index a1b9be1d105a..fde4edd83c14 100644
--- a/drivers/soc/fsl/qbman/qman.c
+++ b/drivers/soc/fsl/qbman/qman.c
@@ -186,7 +186,7 @@ struct qm_eqcr_entry {
__be32 tag;
struct qm_fd fd;
u8 __reserved3[32];
-} __packed;
+} __packed __aligned(8);
#define QM_EQCR_VERB_VBIT 0x80
#define QM_EQCR_VERB_CMD_MASK 0x61 /* but only one value; */
#define QM_EQCR_VERB_CMD_ENQUEUE 0x01
--
2.29.2
^ permalink raw reply related
* Re: [PATCH v11 0/6] KASAN for powerpc64 radix
From: Christophe Leroy @ 2021-03-23 13:27 UTC (permalink / raw)
To: Daniel Axtens, linux-kernel, linux-mm, linuxppc-dev, kasan-dev,
aneesh.kumar, bsingharora
In-Reply-To: <87ft0mbr6r.fsf@dja-thinkpad.axtens.net>
Le 23/03/2021 à 02:21, Daniel Axtens a écrit :
> Hi Christophe,
>
>> In the discussion we had long time ago,
>> https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20190806233827.16454-5-dja@axtens.net/#2321067
>> , I challenged you on why it was not possible to implement things the same way as other
>> architectures, in extenso with an early mapping.
>>
>> Your first answer was that too many things were done in real mode at startup. After some discussion
>> you said that finally there was not that much things at startup but the issue was KVM.
>>
>> Now you say that instrumentation on KVM is fully disabled.
>>
>> So my question is, if KVM is not a problem anymore, why not go the standard way with an early shadow
>> ? Then you could also support inline instrumentation.
>
> Fair enough, I've had some trouble both understanding the problem myself
> and clearly articulating it. Let me try again.
>
> We need translations on to access the shadow area.
>
> We reach setup_64.c::early_setup() with translations off. At this point
> we don't know what MMU we're running under, or our CPU features.
What do you need to know ? Whether it is Hash or Radix, or more/different details ?
IIUC, today we only support KASAN on Radix. Would it make sense to say that a kernel built with
KASAN can only run on processors having Radix capacility ? Then select CONFIG_PPC_RADIX_MMU_DEFAULT
when KASAN is set, and accept that the kernel crashes if Radix is not available ?
>
> To determine our MMU and CPU features, early_setup() calls functions
> (dt_cpu_ftrs_init, early_init_devtree) that call out to generic code
> like of_scan_flat_dt. We need to do this before we turn on translations
> because we can't set up the MMU until we know what MMU we have.
>
> So this puts us in a bind:
>
> - We can't set up an early shadow until we have translations on, which
> requires that the MMU is set up.
>
> - We can't set up an MMU until we call out to generic code for FDT
> parsing.
>
> So there will be calls to generic FDT parsing code that happen before the
> early shadow is set up.
I see some logic in kernel/prom_init.c for detecting MMU. Can we get the information from there in
order to setup the MMU ?
>
> The setup code also prints a bunch of information about the platform
> with printk() while translations are off, so it wouldn't even be enough
> to disable instrumentation for bits of the generic DT code on ppc64.
I'm sure the printk() stuff can be avoided or delayed without much problems, I guess the main
problem is the DT code, isn't it ?
As far as I can see the code only use udbg_printf() before MMU is on, and this could be simply
skipped when KASAN is selected, I see no situation where you need early printk together with KASAN.
>
> Does that make sense? If you can figure out how to 'square the circle'
> here I'm all ears.
Yes it is a lot more clear now, thanks you. Gave a few ideas above, does it help ?
>
> Other notes:
>
> - There's a comment about printk() being 'safe' in early_setup(), that
> refers to having a valid PACA, it doesn't mean that it's safe in any
> other sense.
>
> - KVM does indeed also run stuff with translations off but we can catch
> all of that by disabling instrumentation on the real-mode handlers:
> it doesn't seem to leak out to generic code. So you are right that
> KVM is no longer an issue.
>
Christophe
^ permalink raw reply
* Re: [PATCH v4 22/46] KVM: PPC: Book3S HV P9: Stop handling hcalls in real-mode in the P9 path
From: Cédric Le Goater @ 2021-03-23 13:23 UTC (permalink / raw)
To: Nicholas Piggin, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <20210323010305.1045293-23-npiggin@gmail.com>
On 3/23/21 2:02 AM, Nicholas Piggin wrote:
> In the interest of minimising the amount of code that is run in
> "real-mode", don't handle hcalls in real mode in the P9 path.
>
> POWER8 and earlier are much more expensive to exit from HV real mode
> and switch to host mode, because on those processors HV interrupts get
> to the hypervisor with the MMU off, and the other threads in the core
> need to be pulled out of the guest, and SLBs all need to be saved,
> ERATs invalidated, and host SLB reloaded before the MMU is re-enabled
> in host mode. Hash guests also require a lot of hcalls to run. The
> XICS interrupt controller requires hcalls to run.
>
> By contrast, POWER9 has independent thread switching, and in radix mode
> the hypervisor is already in a host virtual memory mode when the HV
> interrupt is taken. Radix + xive guests don't need hcalls to handle
> interrupts or manage translations.
>
> So it's much less important to handle hcalls in real mode in P9.
>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
> arch/powerpc/include/asm/kvm_ppc.h | 5 ++
> arch/powerpc/kvm/book3s_hv.c | 57 ++++++++++++++++----
> arch/powerpc/kvm/book3s_hv_rmhandlers.S | 5 ++
> arch/powerpc/kvm/book3s_xive.c | 70 +++++++++++++++++++++++++
> 4 files changed, 127 insertions(+), 10 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
> index 73b1ca5a6471..db6646c2ade2 100644
> --- a/arch/powerpc/include/asm/kvm_ppc.h
> +++ b/arch/powerpc/include/asm/kvm_ppc.h
> @@ -607,6 +607,7 @@ extern void kvmppc_free_pimap(struct kvm *kvm);
> extern int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall);
> extern void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu);
> extern int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd);
> +extern int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req);
> extern u64 kvmppc_xics_get_icp(struct kvm_vcpu *vcpu);
> extern int kvmppc_xics_set_icp(struct kvm_vcpu *vcpu, u64 icpval);
> extern int kvmppc_xics_connect_vcpu(struct kvm_device *dev,
> @@ -639,6 +640,8 @@ static inline int kvmppc_xics_enabled(struct kvm_vcpu *vcpu)
> static inline void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu) { }
> static inline int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd)
> { return 0; }
> +static inline int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req)
> + { return 0; }
> #endif
>
> #ifdef CONFIG_KVM_XIVE
> @@ -673,6 +676,7 @@ extern int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq,
> int level, bool line_status);
> extern void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu);
> extern void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu);
> +extern void kvmppc_xive_cede_vcpu(struct kvm_vcpu *vcpu);
>
> static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
> {
> @@ -714,6 +718,7 @@ static inline int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 ir
> int level, bool line_status) { return -ENODEV; }
> static inline void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu) { }
> static inline void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu) { }
> +static inline void kvmppc_xive_cede_vcpu(struct kvm_vcpu *vcpu) { }
>
> static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
> { return 0; }
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index fa7614c37e08..17739aaee3d8 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -1142,12 +1142,13 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
> }
>
> /*
> - * Handle H_CEDE in the nested virtualization case where we haven't
> - * called the real-mode hcall handlers in book3s_hv_rmhandlers.S.
> + * Handle H_CEDE in the P9 path where we don't call the real-mode hcall
> + * handlers in book3s_hv_rmhandlers.S.
> + *
> * This has to be done early, not in kvmppc_pseries_do_hcall(), so
> * that the cede logic in kvmppc_run_single_vcpu() works properly.
> */
> -static void kvmppc_nested_cede(struct kvm_vcpu *vcpu)
> +static void kvmppc_cede(struct kvm_vcpu *vcpu)
> {
> vcpu->arch.shregs.msr |= MSR_EE;
> vcpu->arch.ceded = 1;
> @@ -1403,9 +1404,15 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu,
> /* hcall - punt to userspace */
> int i;
>
> - /* hypercall with MSR_PR has already been handled in rmode,
> - * and never reaches here.
> - */
> + if (unlikely(vcpu->arch.shregs.msr & MSR_PR)) {
> + /*
> + * Guest userspace executed sc 1, reflect it back as a
> + * privileged program check interrupt.
> + */
> + kvmppc_core_queue_program(vcpu, SRR1_PROGPRIV);
> + r = RESUME_GUEST;
> + break;
> + }
>
> run->papr_hcall.nr = kvmppc_get_gpr(vcpu, 3);
> for (i = 0; i < 9; ++i)
> @@ -3663,6 +3670,12 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit,
> return trap;
> }
>
> +static inline bool hcall_is_xics(unsigned long req)
> +{
> + return (req == H_EOI || req == H_CPPR || req == H_IPI ||
> + req == H_IPOLL || req == H_XIRR || req == H_XIRR_X);
> +}
> +
> /*
> * Virtual-mode guest entry for POWER9 and later when the host and
> * guest are both using the radix MMU. The LPIDR has already been set.
> @@ -3774,15 +3787,36 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
> /* H_CEDE has to be handled now, not later */
> if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
> kvmppc_get_gpr(vcpu, 3) == H_CEDE) {
> - kvmppc_nested_cede(vcpu);
> + kvmppc_cede(vcpu);
> kvmppc_set_gpr(vcpu, 3, 0);
> trap = 0;
> }
> } else {
> kvmppc_xive_push_vcpu(vcpu);
> trap = kvmhv_load_hv_regs_and_go(vcpu, time_limit, lpcr);
> + if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
> + !(vcpu->arch.shregs.msr & MSR_PR)) {
> + unsigned long req = kvmppc_get_gpr(vcpu, 3);
> +
> + /* H_CEDE has to be handled now, not later */
> + if (req == H_CEDE) {
> + kvmppc_cede(vcpu);
> + kvmppc_xive_cede_vcpu(vcpu); /* may un-cede */> + kvmppc_set_gpr(vcpu, 3, 0);
> + trap = 0;
> +
> + /* XICS hcalls must be handled before xive is pulled */
> + } else if (hcall_is_xics(req)) {
> + int ret;
> +
> + ret = kvmppc_xive_xics_hcall(vcpu, req);
> + if (ret != H_TOO_HARD) {
> + kvmppc_set_gpr(vcpu, 3, ret);
> + trap = 0;
> + }
> + }
> + }
> kvmppc_xive_pull_vcpu(vcpu);
> -
> }
>
> vcpu->arch.slb_max = 0;
> @@ -4442,8 +4476,11 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu)
> else
> r = kvmppc_run_vcpu(vcpu);
>
> - if (run->exit_reason == KVM_EXIT_PAPR_HCALL &&
> - !(vcpu->arch.shregs.msr & MSR_PR)) {
> + if (run->exit_reason == KVM_EXIT_PAPR_HCALL) {
> + if (WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_PR)) {
> + r = RESUME_GUEST;
> + continue;
> + }
> trace_kvm_hcall_enter(vcpu);
> r = kvmppc_pseries_do_hcall(vcpu);
> trace_kvm_hcall_exit(vcpu, r);
> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> index c11597f815e4..2d0d14ed1d92 100644
> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> @@ -1397,9 +1397,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
> mr r4,r9
> bge fast_guest_return
> 2:
> + /* If we came in through the P9 short path, no real mode hcalls */
> + lwz r0, STACK_SLOT_SHORT_PATH(r1)
> + cmpwi r0, 0
> + bne no_try_real
> /* See if this is an hcall we can handle in real mode */
> cmpwi r12,BOOK3S_INTERRUPT_SYSCALL
> beq hcall_try_real_mode
> +no_try_real:
>
> /* Hypervisor doorbell - exit only if host IPI flag set */
> cmpwi r12, BOOK3S_INTERRUPT_H_DOORBELL
> diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c
> index 741bf1f4387a..dcc07ceaf5ca 100644
> --- a/arch/powerpc/kvm/book3s_xive.c
> +++ b/arch/powerpc/kvm/book3s_xive.c
> @@ -158,6 +158,40 @@ void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu)
> }
> EXPORT_SYMBOL_GPL(kvmppc_xive_pull_vcpu);
>
> +void kvmppc_xive_cede_vcpu(struct kvm_vcpu *vcpu)
kvmppc_xive_rearm_escalation() may be ? It has more meaning to me.
> +{
> + void __iomem *esc_vaddr = (void __iomem *)vcpu->arch.xive_esc_vaddr;
> +
> + if (!esc_vaddr)
> + return;
> +
> + /* we are using XIVE with single escalation */
> +
> + if (vcpu->arch.xive_esc_on) {
> + /*
> + * If we still have a pending escalation, abort the cede,
> + * and we must set PQ to 10 rather than 00 so that we don't
> + * potentially end up with two entries for the escalation
> + * interrupt in the XIVE interrupt queue. In that case
> + * we also don't want to set xive_esc_on to 1 here in
> + * case we race with xive_esc_irq().
> + */
> + vcpu->arch.ceded = 0;
> + /*
> + * The escalation interrupts are special as we don't EOI them.
> + * There is no need to use the load-after-store ordering offset
> + * to set PQ to 10 as we won't use StoreEOI.
> + */
> + __raw_readq(esc_vaddr + XIVE_ESB_SET_PQ_10);
> + } else {
> + vcpu->arch.xive_esc_on = true;> + mb();
> + __raw_readq(esc_vaddr + XIVE_ESB_SET_PQ_00);
> + }
> + mb();
> +}
> +EXPORT_SYMBOL_GPL(kvmppc_xive_cede_vcpu);
> +
> /*
> * This is a simple trigger for a generic XIVE IRQ. This must
> * only be called for interrupts that support a trigger page
> @@ -2106,6 +2140,42 @@ static int kvmppc_xive_create(struct kvm_device *dev, u32 type)
> return 0;
> }
>
> +int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req)
> +{
> + struct kvmppc_vcore *vc = vcpu->arch.vcore;
> +
> + /*
> + * This test covers the case in which a vCPU does XICS hcalls without
> + * QEMU having connected the vCPU to a XICS ICP. The ICP is the KVM
> + * XICS device on P8 or XICS-on-XIVE on P9. It catches QEMU errors when
> + * the interrupt mode is negotiated, we don't want the OS to do XICS
> + * hcalls after having negotiated the XIVE interrupt mode.
> + */
I think a comment like the following should be enough.
The VM should have configured XICS mode before doing XICS hcalls.
No need to resend for that though.
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Thanks,
C.
> + if (!kvmppc_xics_enabled(vcpu))
> + return H_TOO_HARD;
> +
> + switch (req) {
> + case H_XIRR:
> + return xive_vm_h_xirr(vcpu);
> + case H_CPPR:
> + return xive_vm_h_cppr(vcpu, kvmppc_get_gpr(vcpu, 4));
> + case H_EOI:
> + return xive_vm_h_eoi(vcpu, kvmppc_get_gpr(vcpu, 4));
> + case H_IPI:
> + return xive_vm_h_ipi(vcpu, kvmppc_get_gpr(vcpu, 4),
> + kvmppc_get_gpr(vcpu, 5));
> + case H_IPOLL:
> + return xive_vm_h_ipoll(vcpu, kvmppc_get_gpr(vcpu, 4));
> + case H_XIRR_X:
> + xive_vm_h_xirr(vcpu);
> + kvmppc_set_gpr(vcpu, 5, get_tb() + vc->tb_offset);
> + return H_SUCCESS;
> + }
> +
> + return H_UNSUPPORTED;
> +}
> +EXPORT_SYMBOL_GPL(kvmppc_xive_xics_hcall);
> +
> int kvmppc_xive_debug_show_queues(struct seq_file *m, struct kvm_vcpu *vcpu)
> {
> struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
>
^ permalink raw reply
* Re: [PATCH v4 39/46] KVM: PPC: Book3S HV: Remove virt mode checks from real mode handlers
From: Cédric Le Goater @ 2021-03-23 13:38 UTC (permalink / raw)
To: Nicholas Piggin, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <20210323010305.1045293-40-npiggin@gmail.com>
On 3/23/21 2:02 AM, Nicholas Piggin wrote:
> Now that the P7/8 path no longer supports radix, real-mode handlers
> do not need to deal with being called in virt mode.
>
> This change effectively reverts commit acde25726bc6 ("KVM: PPC: Book3S
> HV: Add radix checks in real-mode hypercall handlers").
>
> It removes a few more real-mode tests in rm hcall handlers, which also
> allows the indirect ops for the xive module to be removed from the
> built-in xics rm handlers.
>
> kvmppc_h_random is renamed to kvmppc_rm_h_random to be a bit more
> descriptive of its function.
>
> Cc: Cédric Le Goater <clg@kaod.org>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
> ---
> arch/powerpc/include/asm/kvm_ppc.h | 10 +--
> arch/powerpc/kvm/book3s.c | 11 +--
> arch/powerpc/kvm/book3s_64_vio_hv.c | 12 ----
> arch/powerpc/kvm/book3s_hv_builtin.c | 91 ++++++-------------------
> arch/powerpc/kvm/book3s_hv_rmhandlers.S | 2 +-
> arch/powerpc/kvm/book3s_xive.c | 18 -----
> arch/powerpc/kvm/book3s_xive.h | 7 --
> arch/powerpc/kvm/book3s_xive_native.c | 10 ---
> 8 files changed, 23 insertions(+), 138 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
> index db6646c2ade2..5dfb3f167f2c 100644
> --- a/arch/powerpc/include/asm/kvm_ppc.h
> +++ b/arch/powerpc/include/asm/kvm_ppc.h
> @@ -659,8 +659,6 @@ extern int kvmppc_xive_get_xive(struct kvm *kvm, u32 irq, u32 *server,
> u32 *priority);
> extern int kvmppc_xive_int_on(struct kvm *kvm, u32 irq);
> extern int kvmppc_xive_int_off(struct kvm *kvm, u32 irq);
> -extern void kvmppc_xive_init_module(void);
> -extern void kvmppc_xive_exit_module(void);
>
> extern int kvmppc_xive_connect_vcpu(struct kvm_device *dev,
> struct kvm_vcpu *vcpu, u32 cpu);
> @@ -686,8 +684,6 @@ static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
> extern int kvmppc_xive_native_connect_vcpu(struct kvm_device *dev,
> struct kvm_vcpu *vcpu, u32 cpu);
> extern void kvmppc_xive_native_cleanup_vcpu(struct kvm_vcpu *vcpu);
> -extern void kvmppc_xive_native_init_module(void);
> -extern void kvmppc_xive_native_exit_module(void);
> extern int kvmppc_xive_native_get_vp(struct kvm_vcpu *vcpu,
> union kvmppc_one_reg *val);
> extern int kvmppc_xive_native_set_vp(struct kvm_vcpu *vcpu,
> @@ -701,8 +697,6 @@ static inline int kvmppc_xive_get_xive(struct kvm *kvm, u32 irq, u32 *server,
> u32 *priority) { return -1; }
> static inline int kvmppc_xive_int_on(struct kvm *kvm, u32 irq) { return -1; }
> static inline int kvmppc_xive_int_off(struct kvm *kvm, u32 irq) { return -1; }
> -static inline void kvmppc_xive_init_module(void) { }
> -static inline void kvmppc_xive_exit_module(void) { }
>
> static inline int kvmppc_xive_connect_vcpu(struct kvm_device *dev,
> struct kvm_vcpu *vcpu, u32 cpu) { return -EBUSY; }
> @@ -725,8 +719,6 @@ static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
> static inline int kvmppc_xive_native_connect_vcpu(struct kvm_device *dev,
> struct kvm_vcpu *vcpu, u32 cpu) { return -EBUSY; }
> static inline void kvmppc_xive_native_cleanup_vcpu(struct kvm_vcpu *vcpu) { }
> -static inline void kvmppc_xive_native_init_module(void) { }
> -static inline void kvmppc_xive_native_exit_module(void) { }
> static inline int kvmppc_xive_native_get_vp(struct kvm_vcpu *vcpu,
> union kvmppc_one_reg *val)
> { return 0; }
> @@ -762,7 +754,7 @@ long kvmppc_rm_h_stuff_tce(struct kvm_vcpu *vcpu,
> unsigned long tce_value, unsigned long npages);
> long int kvmppc_rm_h_confer(struct kvm_vcpu *vcpu, int target,
> unsigned int yield_count);
> -long kvmppc_h_random(struct kvm_vcpu *vcpu);
> +long kvmppc_rm_h_random(struct kvm_vcpu *vcpu);
> void kvmhv_commence_exit(int trap);
> void kvmppc_realmode_machine_check(struct kvm_vcpu *vcpu);
> void kvmppc_subcore_enter_guest(void);
> diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
> index 44bf567b6589..1888aedfd410 100644
> --- a/arch/powerpc/kvm/book3s.c
> +++ b/arch/powerpc/kvm/book3s.c
> @@ -1046,13 +1046,10 @@ static int kvmppc_book3s_init(void)
> #ifdef CONFIG_KVM_XICS
> #ifdef CONFIG_KVM_XIVE
> if (xics_on_xive()) {
> - kvmppc_xive_init_module();
> kvm_register_device_ops(&kvm_xive_ops, KVM_DEV_TYPE_XICS);
> - if (kvmppc_xive_native_supported()) {
> - kvmppc_xive_native_init_module();
> + if (kvmppc_xive_native_supported())
> kvm_register_device_ops(&kvm_xive_native_ops,
> KVM_DEV_TYPE_XIVE);
> - }
> } else
> #endif
> kvm_register_device_ops(&kvm_xics_ops, KVM_DEV_TYPE_XICS);
> @@ -1062,12 +1059,6 @@ static int kvmppc_book3s_init(void)
>
> static void kvmppc_book3s_exit(void)
> {
> -#ifdef CONFIG_KVM_XICS
> - if (xics_on_xive()) {
> - kvmppc_xive_exit_module();
> - kvmppc_xive_native_exit_module();
> - }
> -#endif
> #ifdef CONFIG_KVM_BOOK3S_32_HANDLER
> kvmppc_book3s_exit_pr();
> #endif
> diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c
> index 083a4e037718..dc6591548f0c 100644
> --- a/arch/powerpc/kvm/book3s_64_vio_hv.c
> +++ b/arch/powerpc/kvm/book3s_64_vio_hv.c
> @@ -391,10 +391,6 @@ long kvmppc_rm_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
> /* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */
> /* liobn, ioba, tce); */
>
> - /* For radix, we might be in virtual mode, so punt */
> - if (kvm_is_radix(vcpu->kvm))
> - return H_TOO_HARD;
> -
> stt = kvmppc_find_table(vcpu->kvm, liobn);
> if (!stt)
> return H_TOO_HARD;
> @@ -489,10 +485,6 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu,
> bool prereg = false;
> struct kvmppc_spapr_tce_iommu_table *stit;
>
> - /* For radix, we might be in virtual mode, so punt */
> - if (kvm_is_radix(vcpu->kvm))
> - return H_TOO_HARD;
> -
> /*
> * used to check for invalidations in progress
> */
> @@ -602,10 +594,6 @@ long kvmppc_rm_h_stuff_tce(struct kvm_vcpu *vcpu,
> long i, ret;
> struct kvmppc_spapr_tce_iommu_table *stit;
>
> - /* For radix, we might be in virtual mode, so punt */
> - if (kvm_is_radix(vcpu->kvm))
> - return H_TOO_HARD;
> -
> stt = kvmppc_find_table(vcpu->kvm, liobn);
> if (!stt)
> return H_TOO_HARD;
> diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
> index 7a0e33a9c980..8d669a0e15f8 100644
> --- a/arch/powerpc/kvm/book3s_hv_builtin.c
> +++ b/arch/powerpc/kvm/book3s_hv_builtin.c
> @@ -34,21 +34,6 @@
> #include "book3s_xics.h"
> #include "book3s_xive.h"
>
> -/*
> - * The XIVE module will populate these when it loads
> - */
> -unsigned long (*__xive_vm_h_xirr)(struct kvm_vcpu *vcpu);
> -unsigned long (*__xive_vm_h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server);
> -int (*__xive_vm_h_ipi)(struct kvm_vcpu *vcpu, unsigned long server,
> - unsigned long mfrr);
> -int (*__xive_vm_h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr);
> -int (*__xive_vm_h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr);
> -EXPORT_SYMBOL_GPL(__xive_vm_h_xirr);
> -EXPORT_SYMBOL_GPL(__xive_vm_h_ipoll);
> -EXPORT_SYMBOL_GPL(__xive_vm_h_ipi);
> -EXPORT_SYMBOL_GPL(__xive_vm_h_cppr);
> -EXPORT_SYMBOL_GPL(__xive_vm_h_eoi);
> -
> /*
> * Hash page table alignment on newer cpus(CPU_FTR_ARCH_206)
> * should be power of 2.
> @@ -196,16 +181,9 @@ int kvmppc_hwrng_present(void)
> }
> EXPORT_SYMBOL_GPL(kvmppc_hwrng_present);
>
> -long kvmppc_h_random(struct kvm_vcpu *vcpu)
> +long kvmppc_rm_h_random(struct kvm_vcpu *vcpu)
> {
> - int r;
> -
> - /* Only need to do the expensive mfmsr() on radix */
> - if (kvm_is_radix(vcpu->kvm) && (mfmsr() & MSR_IR))
> - r = powernv_get_random_long(&vcpu->arch.regs.gpr[4]);
> - else
> - r = powernv_get_random_real_mode(&vcpu->arch.regs.gpr[4]);
> - if (r)
> + if (powernv_get_random_real_mode(&vcpu->arch.regs.gpr[4]))
> return H_SUCCESS;
>
> return H_HARDWARE;
> @@ -541,22 +519,13 @@ static long kvmppc_read_one_intr(bool *again)
> }
>
> #ifdef CONFIG_KVM_XICS
> -static inline bool is_rm(void)
> -{
> - return !(mfmsr() & MSR_DR);
> -}
> -
> unsigned long kvmppc_rm_h_xirr(struct kvm_vcpu *vcpu)
> {
> if (!kvmppc_xics_enabled(vcpu))
> return H_TOO_HARD;
> - if (xics_on_xive()) {
> - if (is_rm())
> - return xive_rm_h_xirr(vcpu);
> - if (unlikely(!__xive_vm_h_xirr))
> - return H_NOT_AVAILABLE;
> - return __xive_vm_h_xirr(vcpu);
> - } else
> + if (xics_on_xive())
> + return xive_rm_h_xirr(vcpu);
> + else
> return xics_rm_h_xirr(vcpu);
> }
>
> @@ -565,13 +534,9 @@ unsigned long kvmppc_rm_h_xirr_x(struct kvm_vcpu *vcpu)
> if (!kvmppc_xics_enabled(vcpu))
> return H_TOO_HARD;
> vcpu->arch.regs.gpr[5] = get_tb();
> - if (xics_on_xive()) {
> - if (is_rm())
> - return xive_rm_h_xirr(vcpu);
> - if (unlikely(!__xive_vm_h_xirr))
> - return H_NOT_AVAILABLE;
> - return __xive_vm_h_xirr(vcpu);
> - } else
> + if (xics_on_xive())
> + return xive_rm_h_xirr(vcpu);
> + else
> return xics_rm_h_xirr(vcpu);
> }
>
> @@ -579,13 +544,9 @@ unsigned long kvmppc_rm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server)
> {
> if (!kvmppc_xics_enabled(vcpu))
> return H_TOO_HARD;
> - if (xics_on_xive()) {
> - if (is_rm())
> - return xive_rm_h_ipoll(vcpu, server);
> - if (unlikely(!__xive_vm_h_ipoll))
> - return H_NOT_AVAILABLE;
> - return __xive_vm_h_ipoll(vcpu, server);
> - } else
> + if (xics_on_xive())
> + return xive_rm_h_ipoll(vcpu, server);
> + else
> return H_TOO_HARD;
> }
>
> @@ -594,13 +555,9 @@ int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
> {
> if (!kvmppc_xics_enabled(vcpu))
> return H_TOO_HARD;
> - if (xics_on_xive()) {
> - if (is_rm())
> - return xive_rm_h_ipi(vcpu, server, mfrr);
> - if (unlikely(!__xive_vm_h_ipi))
> - return H_NOT_AVAILABLE;
> - return __xive_vm_h_ipi(vcpu, server, mfrr);
> - } else
> + if (xics_on_xive())
> + return xive_rm_h_ipi(vcpu, server, mfrr);
> + else
> return xics_rm_h_ipi(vcpu, server, mfrr);
> }
>
> @@ -608,13 +565,9 @@ int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr)
> {
> if (!kvmppc_xics_enabled(vcpu))
> return H_TOO_HARD;
> - if (xics_on_xive()) {
> - if (is_rm())
> - return xive_rm_h_cppr(vcpu, cppr);
> - if (unlikely(!__xive_vm_h_cppr))
> - return H_NOT_AVAILABLE;
> - return __xive_vm_h_cppr(vcpu, cppr);
> - } else
> + if (xics_on_xive())
> + return xive_rm_h_cppr(vcpu, cppr);
> + else
> return xics_rm_h_cppr(vcpu, cppr);
> }
>
> @@ -622,13 +575,9 @@ int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
> {
> if (!kvmppc_xics_enabled(vcpu))
> return H_TOO_HARD;
> - if (xics_on_xive()) {
> - if (is_rm())
> - return xive_rm_h_eoi(vcpu, xirr);
> - if (unlikely(!__xive_vm_h_eoi))
> - return H_NOT_AVAILABLE;
> - return __xive_vm_h_eoi(vcpu, xirr);
> - } else
> + if (xics_on_xive())
> + return xive_rm_h_eoi(vcpu, xirr);
> + else
> return xics_rm_h_eoi(vcpu, xirr);
> }
> #endif /* CONFIG_KVM_XICS */
> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> index b1f3ee16fd84..564ca9feef35 100644
> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> @@ -2323,7 +2323,7 @@ hcall_real_table:
> #else
> .long 0 /* 0x2fc - H_XIRR_X*/
> #endif
> - .long DOTSYM(kvmppc_h_random) - hcall_real_table
> + .long DOTSYM(kvmppc_rm_h_random) - hcall_real_table
> .globl hcall_real_table_end
> hcall_real_table_end:
>
> diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c
> index dcc07ceaf5ca..80d32b4eb898 100644
> --- a/arch/powerpc/kvm/book3s_xive.c
> +++ b/arch/powerpc/kvm/book3s_xive.c
> @@ -2358,21 +2358,3 @@ struct kvm_device_ops kvm_xive_ops = {
> .get_attr = xive_get_attr,
> .has_attr = xive_has_attr,
> };
> -
> -void kvmppc_xive_init_module(void)
> -{
> - __xive_vm_h_xirr = xive_vm_h_xirr;
> - __xive_vm_h_ipoll = xive_vm_h_ipoll;
> - __xive_vm_h_ipi = xive_vm_h_ipi;
> - __xive_vm_h_cppr = xive_vm_h_cppr;
> - __xive_vm_h_eoi = xive_vm_h_eoi;
> -}
> -
> -void kvmppc_xive_exit_module(void)
> -{
> - __xive_vm_h_xirr = NULL;
> - __xive_vm_h_ipoll = NULL;
> - __xive_vm_h_ipi = NULL;
> - __xive_vm_h_cppr = NULL;
> - __xive_vm_h_eoi = NULL;
> -}
> diff --git a/arch/powerpc/kvm/book3s_xive.h b/arch/powerpc/kvm/book3s_xive.h
> index 86c24a4ad809..afe9eeac6d56 100644
> --- a/arch/powerpc/kvm/book3s_xive.h
> +++ b/arch/powerpc/kvm/book3s_xive.h
> @@ -289,13 +289,6 @@ extern int xive_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
> extern int xive_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr);
> extern int xive_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr);
>
> -extern unsigned long (*__xive_vm_h_xirr)(struct kvm_vcpu *vcpu);
> -extern unsigned long (*__xive_vm_h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server);
> -extern int (*__xive_vm_h_ipi)(struct kvm_vcpu *vcpu, unsigned long server,
> - unsigned long mfrr);
> -extern int (*__xive_vm_h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr);
> -extern int (*__xive_vm_h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr);
> -
> /*
> * Common Xive routines for XICS-over-XIVE and XIVE native
> */
> diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c
> index 76800c84f2a3..1253666dd4d8 100644
> --- a/arch/powerpc/kvm/book3s_xive_native.c
> +++ b/arch/powerpc/kvm/book3s_xive_native.c
> @@ -1281,13 +1281,3 @@ struct kvm_device_ops kvm_xive_native_ops = {
> .has_attr = kvmppc_xive_native_has_attr,
> .mmap = kvmppc_xive_native_mmap,
> };
> -
> -void kvmppc_xive_native_init_module(void)
> -{
> - ;
> -}
> -
> -void kvmppc_xive_native_exit_module(void)
> -{
> - ;
> -}
>
^ permalink raw reply
* Re: [PATCH 02/10] ARM: disable CONFIG_IDE in footbridge_defconfig
From: Russell King - ARM Linux admin @ 2021-03-23 14:03 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Jens Axboe, Thomas Bogendoerfer, linux-doc, linux-kernel,
linux-mips, linux-ide, linux-m68k, Ivan Kokshaysky, linux-alpha,
Geert Uytterhoeven, Matt Turner, linuxppc-dev, David S. Miller,
linux-arm-kernel, Richard Henderson
In-Reply-To: <20210322153314.GA3440@lst.de>
On Mon, Mar 22, 2021 at 04:33:14PM +0100, Christoph Hellwig wrote:
> On Mon, Mar 22, 2021 at 04:18:23PM +0100, Christoph Hellwig wrote:
> > On Mon, Mar 22, 2021 at 03:15:03PM +0000, Russell King - ARM Linux admin wrote:
> > > It gets worse than that though - due to a change to remove
> > > pcibios_min_io from the generic code, moving it into the ARM
> > > architecture code, this has caused a regression that prevents the
> > > legacy resources being registered against the bus resource. So even
> > > if they are there, they cause probe failures. I haven't found a
> > > reasonable way to solve this yet, but until there is, there is no
> > > way that the PATA driver can be used as the "legacy mode" support
> > > is effectively done via the PCI code assigning virtual IO port
> > > resources.
> > >
> > > I'm quite surprised that the CY82C693 even works on Alpha - I've
> > > asked for a lspci for that last week but nothing has yet been
> > > forthcoming from whoever responded to your patch for Alpha - so I
> > > can't compare what I'm seeing with what's happening with Alpha.
> >
> > That sounds like something we could fix with a quirk for function 2
> > in the PCI resource assignment code. Can you show what vendor and
> > device ID function 2 has so that I could try to come up with one?
>
> Something like this:
That solves the problem for the IDE driver, which knows how to deal
with legacy mode, but not the PATA driver, which doesn't. The PATA
driver needs these resources.
As I say, having these resources presents a problem on ARM. A previous
commit (3c5d1699887b) changed the way the bus resources are setup which
results in /proc/ioports containing:
00000000-0000000f : dma1
00000020-0000003f : pic1
00000060-0000006f : i8042
00000070-00000073 : rtc_cmos
00000070-00000073 : rtc0
00000080-0000008f : dma low page
000000a0-000000bf : pic2
000000c0-000000df : dma2
00000213-00000213 : ISAPnP
000002f8-000002ff : serial8250.0
000002f8-000002ff : serial
000003c0-000003df : vga+
000003f8-000003ff : serial8250.0
000003f8-000003ff : serial
00000480-0000048f : dma high page
00000a79-00000a79 : isapnp write
00001000-0000ffff : PCI0 I/O
00001000-0000107f : 0000:00:08.0
00001000-0000107f : 3c59x
00001080-0000108f : 0000:00:06.1
00001090-0000109f : 0000:00:07.0
00001090-0000109f : pata_it821x
000010a0-000010a7 : 0000:00:07.0
000010a0-000010a7 : pata_it821x
000010a8-000010af : 0000:00:07.0
000010a8-000010af : pata_it821x
000010b0-000010b3 : 0000:00:07.0
000010b0-000010b3 : pata_it821x
000010b4-000010b7 : 0000:00:07.0
000010b4-000010b7 : pata_it821x
The "PCI0 I/O" resource is the bus level resource, and the legacy
resources can not be claimed against that.
Without these resources, the PATA cypress driver doesn't work.
As I said previously, the reason this regression was not picked up
earlier is because I don't upgrade the kernel on this machine very
often; the machine has had uptimes into thousands of days.
I need to try reverting Rob's commit to find out if anything breaks
on this platform - it's completely wrong from a technical point of
view for any case where we have a PCI southbridge, since the
southbridge provides ISA based resources. I'm not entirely sure
what the point of it was, since we still have the PCIBIOS_MIN_IO
macro which still uses pcibios_min_io.
I'm looking at some of the other changes Rob made back at that time
which also look wrong, such as 8ef6e6201b26 which has the effect of
locating the 21285 IO resources to PCI address 0, over the top of
the ISA southbridge resources. I've no idea what Rob was thinking
when he removed the csrio allocation code in that commit, but
looking at it to day, it's soo obviously wrong even to a casual
glance.
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
^ permalink raw reply
* Re: [PATCH 0/4] Rust for Linux for ppc64le
From: Miguel Ojeda @ 2021-03-23 14:26 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, linux-kernel, rust-for-linux
In-Reply-To: <87mtuugj61.fsf@mpe.ellerman.id.au>
On Tue, Mar 23, 2021 at 1:16 PM Michael Ellerman <mpe@ellerman.id.au> wrote:
>
> It would be nice to be in the CI. I was building natively so I haven't
> tried cross compiling yet (which we'll need for CI).
Indeed -- in the CI we already cross-compile arm64 (and run under QEMU
both arm64 as well as x86_64), so it is easy to add new ones to the
matrix.
> I can send a pull request if that's easiest.
No worries, I will pick the patches. But, of course, feel free to join
us in GitHub! :-)
Cheers,
Miguel
^ permalink raw reply
* [PATCH] powerpc: Switch to relative jump labels
From: Christophe Leroy @ 2021-03-23 15:47 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
Convert powerpc to relative jump labels.
Before the patch, pseries_defconfig vmlinux.o has:
9074 __jump_table 0003f2a0 0000000000000000 0000000000000000 01321fa8 2**0
With the patch, the same config gets:
9074 __jump_table 0002a0e0 0000000000000000 0000000000000000 01321fb4 2**0
Size is 258720 without the patch, 172256 with the patch.
That's a 33% size reduction.
Largely copied from commit c296146c058c ("arm64/kernel: jump_label:
Switch to relative references")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/jump_label.h | 21 ++++++---------------
arch/powerpc/kernel/jump_label.c | 4 ++--
3 files changed, 9 insertions(+), 17 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index d46db0bfb998..a52938c0f85b 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -182,6 +182,7 @@ config PPC
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_HUGE_VMAP if PPC_BOOK3S_64 && PPC_RADIX_MMU
select HAVE_ARCH_JUMP_LABEL
+ select HAVE_ARCH_JUMP_LABEL_RELATIVE
select HAVE_ARCH_KASAN if PPC32 && PPC_PAGE_SHIFT <= 14
select HAVE_ARCH_KASAN_VMALLOC if PPC32 && PPC_PAGE_SHIFT <= 14
select HAVE_ARCH_KGDB
diff --git a/arch/powerpc/include/asm/jump_label.h b/arch/powerpc/include/asm/jump_label.h
index 09297ec9fa52..2d5c6bec2b4f 100644
--- a/arch/powerpc/include/asm/jump_label.h
+++ b/arch/powerpc/include/asm/jump_label.h
@@ -20,7 +20,8 @@ static __always_inline bool arch_static_branch(struct static_key *key, bool bran
asm_volatile_goto("1:\n\t"
"nop # arch_static_branch\n\t"
".pushsection __jump_table, \"aw\"\n\t"
- JUMP_ENTRY_TYPE "1b, %l[l_yes], %c0\n\t"
+ ".long 1b - ., %l[l_yes] - .\n\t"
+ JUMP_ENTRY_TYPE "%c0 - .\n\t"
".popsection \n\t"
: : "i" (&((char *)key)[branch]) : : l_yes);
@@ -34,7 +35,8 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool
asm_volatile_goto("1:\n\t"
"b %l[l_yes] # arch_static_branch_jump\n\t"
".pushsection __jump_table, \"aw\"\n\t"
- JUMP_ENTRY_TYPE "1b, %l[l_yes], %c0\n\t"
+ ".long 1b - ., %l[l_yes] - .\n\t"
+ JUMP_ENTRY_TYPE "%c0 - .\n\t"
".popsection \n\t"
: : "i" (&((char *)key)[branch]) : : l_yes);
@@ -43,23 +45,12 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool
return true;
}
-#ifdef CONFIG_PPC64
-typedef u64 jump_label_t;
-#else
-typedef u32 jump_label_t;
-#endif
-
-struct jump_entry {
- jump_label_t code;
- jump_label_t target;
- jump_label_t key;
-};
-
#else
#define ARCH_STATIC_BRANCH(LABEL, KEY) \
1098: nop; \
.pushsection __jump_table, "aw"; \
- FTR_ENTRY_LONG 1098b, LABEL, KEY; \
+ .long 1098b - ., LABEL - .; \
+ FTR_ENTRY_LONG KEY; \
.popsection
#endif
diff --git a/arch/powerpc/kernel/jump_label.c b/arch/powerpc/kernel/jump_label.c
index 144858027fa3..ce87dc5ea23c 100644
--- a/arch/powerpc/kernel/jump_label.c
+++ b/arch/powerpc/kernel/jump_label.c
@@ -11,10 +11,10 @@
void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
- struct ppc_inst *addr = (struct ppc_inst *)(unsigned long)entry->code;
+ struct ppc_inst *addr = (struct ppc_inst *)jump_entry_code(entry);
if (type == JUMP_LABEL_JMP)
- patch_branch(addr, entry->target, 0);
+ patch_branch(addr, jump_entry_target(entry), 0);
else
patch_instruction(addr, ppc_inst(PPC_INST_NOP));
}
--
2.25.0
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