From 7ede531773ea69fa56b02a873ed83ce3507eb8d5 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 22 Dec 2016 04:29:26 +1000 Subject: KVM: PPC: Book3S: Move 64-bit KVM interrupt handler out from alt section A subsequent patch to make KVM handlers relocation-safe makes them unusable from within alt section "else" cases (due to the way fixed addresses are taken from within fixed section head code). Stop open-coding the KVM handlers, and add them both as normal. A more optimal fix may be to allow some level of alternate feature patching in the exception macros themselves, but for now this will do. The TRAMP_KVM handlers must be moved to the "virt" fixed section area (name is arbitrary) in order to be closer to .text and avoid the dreaded "relocation truncated to fit" error. Signed-off-by: Nicholas Piggin Acked-by: Paul Mackerras Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/exceptions-64s.S | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'arch/powerpc/kernel/exceptions-64s.S') diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index d39d6118c6e9..89b4f122aec6 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -717,13 +717,9 @@ hardware_interrupt_hv: BEGIN_FTR_SECTION _MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt_common, EXC_HV, SOFTEN_TEST_HV) -do_kvm_H0x500: - KVM_HANDLER(PACA_EXGEN, EXC_HV, 0x502) FTR_SECTION_ELSE _MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt_common, EXC_STD, SOFTEN_TEST_PR) -do_kvm_0x500: - KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x500) ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206) EXC_REAL_END(hardware_interrupt, 0x500, 0x600) @@ -737,6 +733,8 @@ hardware_interrupt_relon_hv: ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE) EXC_VIRT_END(hardware_interrupt, 0x4500, 0x4600) +TRAMP_KVM(PACA_EXGEN, 0x500) +TRAMP_KVM_HV(PACA_EXGEN, 0x500) EXC_COMMON_ASYNC(hardware_interrupt_common, 0x500, do_IRQ) -- cgit From a97a65d53d9f53b6897dc1b2aed381bc1707136b Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 27 Jan 2017 14:00:34 +1000 Subject: KVM: PPC: Book3S: 64-bit CONFIG_RELOCATABLE support for interrupts 64-bit Book3S exception handlers must find the dynamic kernel base to add to the target address when branching beyond __end_interrupts, in order to support kernel running at non-0 physical address. Support this in KVM by branching with CTR, similarly to regular interrupt handlers. The guest CTR saved in HSTATE_SCRATCH1 and restored after the branch. Without this, the host kernel hangs and crashes randomly when it is running at a non-0 address and a KVM guest is started. Signed-off-by: Nicholas Piggin Acked-by: Paul Mackerras Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/exceptions-64s.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/powerpc/kernel/exceptions-64s.S') diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 89b4f122aec6..65a2559eeb7f 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -142,7 +142,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300) lbz r0,HSTATE_HWTHREAD_REQ(r13) cmpwi r0,0 beq 1f - b kvm_start_guest + BRANCH_TO_KVM(r10, kvm_start_guest) 1: #endif -- cgit From bc3551257af837fc603d295e59f9e32953525b98 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Mon, 30 Jan 2017 21:21:40 +1100 Subject: powerpc/64: Allow for relocation-on interrupts from guest to host With host and guest both using radix translation, it is feasible for the host to take interrupts that come from the guest with relocation on, and that is in fact what the POWER9 hardware will do when LPCR[AIL] = 3. All such interrupts use HSRR0/1 not SRR0/1 except for system call with LEV=1 (hcall). Therefore this adds the KVM tests to the _HV variants of the relocation-on interrupt handlers, and adds the KVM test to the relocation-on system call entry point. We also instantiate the relocation-on versions of the hypervisor data storage and instruction interrupt handlers, since these can occur with relocation on in radix guests. Signed-off-by: Paul Mackerras Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/exceptions-64s.S | 53 ++++++++++++++++++++---------------- 1 file changed, 29 insertions(+), 24 deletions(-) (limited to 'arch/powerpc/kernel/exceptions-64s.S') diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 65a2559eeb7f..34a04a5fa468 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -830,6 +830,31 @@ EXC_VIRT(trap_0b, 0x4b00, 0x4c00, 0xb00) TRAMP_KVM(PACA_EXGEN, 0xb00) EXC_COMMON(trap_0b_common, 0xb00, unknown_exception) +#ifdef CONFIG_KVM_BOOK3S_64_HANDLER + /* + * If CONFIG_KVM_BOOK3S_64_HANDLER is set, save the PPR (on systems + * that support it) before changing to HMT_MEDIUM. That allows the KVM + * code to save that value into the guest state (it is the guest's PPR + * value). Otherwise just change to HMT_MEDIUM as userspace has + * already saved the PPR. + */ +#define SYSCALL_KVMTEST \ + SET_SCRATCH0(r13); \ + GET_PACA(r13); \ + std r9,PACA_EXGEN+EX_R9(r13); \ + OPT_GET_SPR(r9, SPRN_PPR, CPU_FTR_HAS_PPR); \ + HMT_MEDIUM; \ + std r10,PACA_EXGEN+EX_R10(r13); \ + OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r9, CPU_FTR_HAS_PPR); \ + mfcr r9; \ + KVMTEST_PR(0xc00); \ + GET_SCRATCH0(r13) + +#else +#define SYSCALL_KVMTEST \ + HMT_MEDIUM +#endif + #define LOAD_SYSCALL_HANDLER(reg) \ __LOAD_HANDLER(reg, system_call_common) @@ -883,34 +908,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) \ #endif EXC_REAL_BEGIN(system_call, 0xc00, 0xd00) - /* - * If CONFIG_KVM_BOOK3S_64_HANDLER is set, save the PPR (on systems - * that support it) before changing to HMT_MEDIUM. That allows the KVM - * code to save that value into the guest state (it is the guest's PPR - * value). Otherwise just change to HMT_MEDIUM as userspace has - * already saved the PPR. - */ -#ifdef CONFIG_KVM_BOOK3S_64_HANDLER - SET_SCRATCH0(r13) - GET_PACA(r13) - std r9,PACA_EXGEN+EX_R9(r13) - OPT_GET_SPR(r9, SPRN_PPR, CPU_FTR_HAS_PPR); - HMT_MEDIUM; - std r10,PACA_EXGEN+EX_R10(r13) - OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r9, CPU_FTR_HAS_PPR); - mfcr r9 - KVMTEST_PR(0xc00) - GET_SCRATCH0(r13) -#else - HMT_MEDIUM; -#endif + SYSCALL_KVMTEST SYSCALL_PSERIES_1 SYSCALL_PSERIES_2_RFID SYSCALL_PSERIES_3 EXC_REAL_END(system_call, 0xc00, 0xd00) EXC_VIRT_BEGIN(system_call, 0x4c00, 0x4d00) - HMT_MEDIUM + SYSCALL_KVMTEST SYSCALL_PSERIES_1 SYSCALL_PSERIES_2_DIRECT SYSCALL_PSERIES_3 @@ -925,7 +930,7 @@ TRAMP_KVM(PACA_EXGEN, 0xd00) EXC_COMMON(single_step_common, 0xd00, single_step_exception) EXC_REAL_OOL_HV(h_data_storage, 0xe00, 0xe20) -EXC_VIRT_NONE(0x4e00, 0x4e20) +EXC_VIRT_OOL_HV(h_data_storage, 0x4e00, 0x4e20, 0xe00) TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0xe00) EXC_COMMON_BEGIN(h_data_storage_common) mfspr r10,SPRN_HDAR @@ -941,7 +946,7 @@ EXC_COMMON_BEGIN(h_data_storage_common) EXC_REAL_OOL_HV(h_instr_storage, 0xe20, 0xe40) -EXC_VIRT_NONE(0x4e20, 0x4e40) +EXC_VIRT_OOL_HV(h_instr_storage, 0x4e20, 0x4e40, 0xe20) TRAMP_KVM_HV(PACA_EXGEN, 0xe20) EXC_COMMON(h_instr_storage_common, 0xe20, unknown_exception) -- cgit From 2337d207288f163e10bd8d4d7eeb0c1c75046a0c Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 27 Jan 2017 14:24:33 +1000 Subject: powerpc/64: CONFIG_RELOCATABLE support for hmi interrupts The branch from hmi_exception_early to hmi_exception_realmode must use a "relocatable-style" branch, because it is branching from unrelocated exception code to beyond __end_interrupts. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/exceptions-64s.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/powerpc/kernel/exceptions-64s.S') diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 34a04a5fa468..76dd7738c122 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -982,7 +982,7 @@ TRAMP_REAL_BEGIN(hmi_exception_early) EXCEPTION_PROLOG_COMMON_2(PACA_EXGEN) EXCEPTION_PROLOG_COMMON_3(0xe60) addi r3,r1,STACK_FRAME_OVERHEAD - bl hmi_exception_realmode + BRANCH_LINK_TO_FAR(r4, hmi_exception_realmode) /* Windup the stack. */ /* Move original HSRR0 and HSRR1 into the respective regs */ ld r9,_MSR(r1) -- cgit