From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bhushan Bharat-R65777 Subject: RE: [PATCH 2/7] Added ONE_REG interface for debug instruction Date: Thu, 14 Mar 2013 04:30:42 +0000 Message-ID: <6A3DF150A5B70D4F9B66A25E3F7C888D065EAA60@039-SN2MPN1-023.039d.mgd.msft.net> References: <1362024796-4237-1-git-send-email-bharat.bhushan@freescale.com> <1362024796-4237-3-git-send-email-bharat.bhushan@freescale.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Cc: "kvm-ppc@vger.kernel.org" , "kvm@vger.kernel.org" , Wood Scott-B07421 To: Alexander Graf Return-path: In-Reply-To: Content-Language: en-US Sender: kvm-ppc-owner@vger.kernel.org List-Id: kvm.vger.kernel.org > -----Original Message----- > From: Alexander Graf [mailto:agraf@suse.de] > Sent: Thursday, March 07, 2013 6:38 PM > To: Bhushan Bharat-R65777 > Cc: kvm-ppc@vger.kernel.org; kvm@vger.kernel.org; Wood Scott-B07421; Bhushan > Bharat-R65777 > Subject: Re: [PATCH 2/7] Added ONE_REG interface for debug instruction > > > On 28.02.2013, at 05:13, Bharat Bhushan wrote: > > > This patch adds the one_reg interface to get the special instruction > > to be used for setting software breakpoint from userspace. > > > > Signed-off-by: Bharat Bhushan > > --- > > Documentation/virtual/kvm/api.txt | 1 + > > arch/powerpc/include/asm/kvm_book3s.h | 1 + > > arch/powerpc/include/asm/kvm_booke.h | 2 ++ > > arch/powerpc/include/uapi/asm/kvm.h | 4 ++++ > > arch/powerpc/kvm/book3s.c | 6 ++++++ > > arch/powerpc/kvm/booke.c | 6 ++++++ > > 6 files changed, 20 insertions(+), 0 deletions(-) > > > > diff --git a/Documentation/virtual/kvm/api.txt > > b/Documentation/virtual/kvm/api.txt > > index cce500a..dbfcc04 100644 > > --- a/Documentation/virtual/kvm/api.txt > > +++ b/Documentation/virtual/kvm/api.txt > > @@ -1766,6 +1766,7 @@ registers, find a list below: > > PPC | KVM_REG_PPC_TSR | 32 > > PPC | KVM_REG_PPC_OR_TSR | 32 > > PPC | KVM_REG_PPC_CLEAR_TSR | 32 > > + PPC | KVM_REG_PPC_DEBUG_INST| 32 > > > > 4.69 KVM_GET_ONE_REG > > > > diff --git a/arch/powerpc/include/asm/kvm_book3s.h > > b/arch/powerpc/include/asm/kvm_book3s.h > > index 5a56e1c..36164cc 100644 > > --- a/arch/powerpc/include/asm/kvm_book3s.h > > +++ b/arch/powerpc/include/asm/kvm_book3s.h > > @@ -458,6 +458,7 @@ static inline bool kvmppc_critical_section(struct kvm_vcpu > *vcpu) > > #define OSI_SC_MAGIC_R4 0x77810F9B > > > > #define INS_DCBZ 0x7c0007ec > > +#define INS_TW 0x7c000008 > > This one should be "trap", so TO needs to be 31. The instruction as it's here is > a nop if I read the spec correctly. Yes I missed this. BTW rather than setting TO = 31, what if we set TO = 2 as RA and RB is same here. -Bharat > > Alex > > > > > /* LPIDs we support with this build -- runtime limit may be lower */ > > #define KVMPPC_NR_LPIDS (LPID_RSVD + 1) > > diff --git a/arch/powerpc/include/asm/kvm_booke.h > > b/arch/powerpc/include/asm/kvm_booke.h > > index b7cd335..d3c1eb3 100644 > > --- a/arch/powerpc/include/asm/kvm_booke.h > > +++ b/arch/powerpc/include/asm/kvm_booke.h > > @@ -26,6 +26,8 @@ > > /* LPIDs we support with this build -- runtime limit may be lower */ > > #define KVMPPC_NR_LPIDS 64 > > > > +#define KVMPPC_INST_EHPRIV 0x7c00021c > > + > > static inline void kvmppc_set_gpr(struct kvm_vcpu *vcpu, int num, > > ulong val) { > > vcpu->arch.gpr[num] = val; > > diff --git a/arch/powerpc/include/uapi/asm/kvm.h > > b/arch/powerpc/include/uapi/asm/kvm.h > > index ef072b1..c2ff99c 100644 > > --- a/arch/powerpc/include/uapi/asm/kvm.h > > +++ b/arch/powerpc/include/uapi/asm/kvm.h > > @@ -422,4 +422,8 @@ struct kvm_get_htab_header { > > #define KVM_REG_PPC_CLEAR_TSR (KVM_REG_PPC | KVM_REG_SIZE_U32 | 0x88) > > #define KVM_REG_PPC_TCR (KVM_REG_PPC | KVM_REG_SIZE_U32 | 0x89) > > #define KVM_REG_PPC_TSR (KVM_REG_PPC | KVM_REG_SIZE_U32 | 0x8a) > > + > > +/* Debugging: Special instruction for software breakpoint */ > > +#define KVM_REG_PPC_DEBUG_INST (KVM_REG_PPC | KVM_REG_SIZE_U32 | 0x8b) > > + > > #endif /* __LINUX_KVM_POWERPC_H */ > > diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c > > index a4b6452..975a401 100644 > > --- a/arch/powerpc/kvm/book3s.c > > +++ b/arch/powerpc/kvm/book3s.c > > @@ -530,6 +530,12 @@ int kvm_vcpu_ioctl_get_one_reg(struct kvm_vcpu *vcpu, > struct kvm_one_reg *reg) > > val = get_reg_val(reg->id, vcpu->arch.vscr.u[3]); > > break; > > #endif /* CONFIG_ALTIVEC */ > > + case KVM_REG_PPC_DEBUG_INST: { > > + u32 opcode = INS_TW; > > + r = copy_to_user((u32 __user *)(long)reg->addr, > > + &opcode, sizeof(u32)); > > + break; > > + } > > default: > > r = -EINVAL; > > break; > > diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index > > 8b553c0..a41cd6d 100644 > > --- a/arch/powerpc/kvm/booke.c > > +++ b/arch/powerpc/kvm/booke.c > > @@ -1448,6 +1448,12 @@ int kvm_vcpu_ioctl_get_one_reg(struct kvm_vcpu *vcpu, > struct kvm_one_reg *reg) > > case KVM_REG_PPC_TSR: > > r = put_user(vcpu->arch.tsr, (u32 __user *)(long)reg->addr); > > break; > > + case KVM_REG_PPC_DEBUG_INST: { > > + u32 opcode = KVMPPC_INST_EHPRIV; > > + r = copy_to_user((u32 __user *)(long)reg->addr, > > + &opcode, sizeof(u32)); > > + break; > > + } > > default: > > break; > > } > > -- > > 1.7.0.4 > > > > > > -- > > To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in > > the body of a message to majordomo@vger.kernel.org More majordomo info > > at http://vger.kernel.org/majordomo-info.html >