diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-19 22:00:23 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-19 22:00:23 +0200 |
commit | 62453a460a000156b100bf20ab78cf77232284d0 (patch) | |
tree | 70c73db399534c85fac1f87e17f0b15982260773 | |
parent | Merge tag 'kbuild-fixes-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/g... (diff) | |
parent | powerpc/xics: Set the IRQ chip data for the ICS native backend (diff) | |
download | linux-62453a460a000156b100bf20ab78cf77232284d0.tar.xz linux-62453a460a000156b100bf20ab78cf77232284d0.zip |
Merge tag 'powerpc-5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- Fix crashes when scv (System Call Vectored) is used to make a syscall
when a transaction is active, on Power9 or later.
- Fix bad interactions between rfscv (Return-from scv) and Power9
fake-suspend mode.
- Fix crashes when handling machine checks in LPARs using the Hash MMU.
- Partly revert a recent change to our XICS interrupt controller code,
which broke the recently added Microwatt support.
Thanks to Cédric Le Goater, Eirik Fuller, Ganesh Goudar, Gustavo Romero,
Joel Stanley, Nicholas Piggin.
* tag 'powerpc-5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/xics: Set the IRQ chip data for the ICS native backend
powerpc/mce: Fix access error in mce handler
KVM: PPC: Book3S HV: Tolerate treclaim. in fake-suspend mode changing registers
powerpc/64s: system call rfscv workaround for TM bugs
selftests/powerpc: Add scv versions of the basic TM syscall tests
powerpc/64s: system call scv tabort fix for corrupt irq soft-mask state
-rw-r--r-- | arch/powerpc/kernel/interrupt.c | 43 | ||||
-rw-r--r-- | arch/powerpc/kernel/interrupt_64.S | 41 | ||||
-rw-r--r-- | arch/powerpc/kernel/mce.c | 17 | ||||
-rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 36 | ||||
-rw-r--r-- | arch/powerpc/sysdev/xics/xics-common.c | 4 | ||||
-rw-r--r-- | tools/testing/selftests/powerpc/tm/tm-syscall-asm.S | 37 | ||||
-rw-r--r-- | tools/testing/selftests/powerpc/tm/tm-syscall.c | 36 |
7 files changed, 159 insertions, 55 deletions
diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c index a73f3f70a657..de10a2697258 100644 --- a/arch/powerpc/kernel/interrupt.c +++ b/arch/powerpc/kernel/interrupt.c @@ -18,6 +18,7 @@ #include <asm/switch_to.h> #include <asm/syscall.h> #include <asm/time.h> +#include <asm/tm.h> #include <asm/unistd.h> #if defined(CONFIG_PPC_ADV_DEBUG_REGS) && defined(CONFIG_PPC32) @@ -136,6 +137,48 @@ notrace long system_call_exception(long r3, long r4, long r5, */ irq_soft_mask_regs_set_state(regs, IRQS_ENABLED); + /* + * If system call is called with TM active, set _TIF_RESTOREALL to + * prevent RFSCV being used to return to userspace, because POWER9 + * TM implementation has problems with this instruction returning to + * transactional state. Final register values are not relevant because + * the transaction will be aborted upon return anyway. Or in the case + * of unsupported_scv SIGILL fault, the return state does not much + * matter because it's an edge case. + */ + if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) && + unlikely(MSR_TM_TRANSACTIONAL(regs->msr))) + current_thread_info()->flags |= _TIF_RESTOREALL; + + /* + * If the system call was made with a transaction active, doom it and + * return without performing the system call. Unless it was an + * unsupported scv vector, in which case it's treated like an illegal + * instruction. + */ +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + if (unlikely(MSR_TM_TRANSACTIONAL(regs->msr)) && + !trap_is_unsupported_scv(regs)) { + /* Enable TM in the kernel, and disable EE (for scv) */ + hard_irq_disable(); + mtmsr(mfmsr() | MSR_TM); + + /* tabort, this dooms the transaction, nothing else */ + asm volatile(".long 0x7c00071d | ((%0) << 16)" + :: "r"(TM_CAUSE_SYSCALL|TM_CAUSE_PERSISTENT)); + + /* + * Userspace will never see the return value. Execution will + * resume after the tbegin. of the aborted transaction with the + * checkpointed register state. A context switch could occur + * or signal delivered to the process before resuming the + * doomed transaction context, but that should all be handled + * as expected. + */ + return -ENOSYS; + } +#endif // CONFIG_PPC_TRANSACTIONAL_MEM + local_irq_enable(); if (unlikely(current_thread_info()->flags & _TIF_SYSCALL_DOTRACE)) { diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S index d4212d2ff0b5..ec950b08a8dc 100644 --- a/arch/powerpc/kernel/interrupt_64.S +++ b/arch/powerpc/kernel/interrupt_64.S @@ -12,7 +12,6 @@ #include <asm/mmu.h> #include <asm/ppc_asm.h> #include <asm/ptrace.h> -#include <asm/tm.h> .section ".toc","aw" SYS_CALL_TABLE: @@ -55,12 +54,6 @@ COMPAT_SYS_CALL_TABLE: .globl system_call_vectored_\name system_call_vectored_\name: _ASM_NOKPROBE_SYMBOL(system_call_vectored_\name) -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM -BEGIN_FTR_SECTION - extrdi. r10, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */ - bne tabort_syscall -END_FTR_SECTION_IFSET(CPU_FTR_TM) -#endif SCV_INTERRUPT_TO_KERNEL mr r10,r1 ld r1,PACAKSAVE(r13) @@ -247,12 +240,6 @@ _ASM_NOKPROBE_SYMBOL(system_call_common_real) .globl system_call_common system_call_common: _ASM_NOKPROBE_SYMBOL(system_call_common) -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM -BEGIN_FTR_SECTION - extrdi. r10, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */ - bne tabort_syscall -END_FTR_SECTION_IFSET(CPU_FTR_TM) -#endif mr r10,r1 ld r1,PACAKSAVE(r13) std r10,0(r1) @@ -425,34 +412,6 @@ SOFT_MASK_TABLE(.Lsyscall_rst_start, 1b) RESTART_TABLE(.Lsyscall_rst_start, .Lsyscall_rst_end, syscall_restart) #endif -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM -tabort_syscall: -_ASM_NOKPROBE_SYMBOL(tabort_syscall) - /* Firstly we need to enable TM in the kernel */ - mfmsr r10 - li r9, 1 - rldimi r10, r9, MSR_TM_LG, 63-MSR_TM_LG - mtmsrd r10, 0 - - /* tabort, this dooms the transaction, nothing else */ - li r9, (TM_CAUSE_SYSCALL|TM_CAUSE_PERSISTENT) - TABORT(R9) - - /* - * Return directly to userspace. We have corrupted user register state, - * but userspace will never see that register state. Execution will - * resume after the tbegin of the aborted transaction with the - * checkpointed register state. - */ - li r9, MSR_RI - andc r10, r10, r9 - mtmsrd r10, 1 - mtspr SPRN_SRR0, r11 - mtspr SPRN_SRR1, r12 - RFI_TO_USER - b . /* prevent speculative execution */ -#endif - /* * If MSR EE/RI was never enabled, IRQs not reconciled, NVGPRs not * touched, no exit work created, then this can be used. diff --git a/arch/powerpc/kernel/mce.c b/arch/powerpc/kernel/mce.c index 47a683cd00d2..fd829f7f25a4 100644 --- a/arch/powerpc/kernel/mce.c +++ b/arch/powerpc/kernel/mce.c @@ -249,6 +249,7 @@ void machine_check_queue_event(void) { int index; struct machine_check_event evt; + unsigned long msr; if (!get_mce_event(&evt, MCE_EVENT_RELEASE)) return; @@ -262,8 +263,20 @@ void machine_check_queue_event(void) memcpy(&local_paca->mce_info->mce_event_queue[index], &evt, sizeof(evt)); - /* Queue irq work to process this event later. */ - irq_work_queue(&mce_event_process_work); + /* + * Queue irq work to process this event later. Before + * queuing the work enable translation for non radix LPAR, + * as irq_work_queue may try to access memory outside RMO + * region. + */ + if (!radix_enabled() && firmware_has_feature(FW_FEATURE_LPAR)) { + msr = mfmsr(); + mtmsr(msr | MSR_IR | MSR_DR); + irq_work_queue(&mce_event_process_work); + mtmsr(msr); + } else { + irq_work_queue(&mce_event_process_work); + } } void mce_common_process_ue(struct pt_regs *regs, diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 75079397c2a5..90484425a1e6 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -2536,7 +2536,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_P9_TM_HV_ASSIST) /* The following code handles the fake_suspend = 1 case */ mflr r0 std r0, PPC_LR_STKOFF(r1) - stdu r1, -PPC_MIN_STKFRM(r1) + stdu r1, -TM_FRAME_SIZE(r1) /* Turn on TM. */ mfmsr r8 @@ -2551,10 +2551,42 @@ BEGIN_FTR_SECTION END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_XER_SO_BUG) nop + /* + * It's possible that treclaim. may modify registers, if we have lost + * track of fake-suspend state in the guest due to it using rfscv. + * Save and restore registers in case this occurs. + */ + mfspr r3, SPRN_DSCR + mfspr r4, SPRN_XER + mfspr r5, SPRN_AMR + /* SPRN_TAR would need to be saved here if the kernel ever used it */ + mfcr r12 + SAVE_NVGPRS(r1) + SAVE_GPR(2, r1) + SAVE_GPR(3, r1) + SAVE_GPR(4, r1) + SAVE_GPR(5, r1) + stw r12, 8(r1) + std r1, HSTATE_HOST_R1(r13) + /* We have to treclaim here because that's the only way to do S->N */ li r3, TM_CAUSE_KVM_RESCHED TRECLAIM(R3) + GET_PACA(r13) + ld r1, HSTATE_HOST_R1(r13) + REST_GPR(2, r1) + REST_GPR(3, r1) + REST_GPR(4, r1) + REST_GPR(5, r1) + lwz r12, 8(r1) + REST_NVGPRS(r1) + mtspr SPRN_DSCR, r3 + mtspr SPRN_XER, r4 + mtspr SPRN_AMR, r5 + mtcr r12 + HMT_MEDIUM + /* * We were in fake suspend, so we are not going to save the * register state as the guest checkpointed state (since @@ -2582,7 +2614,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_XER_SO_BUG) std r5, VCPU_TFHAR(r9) std r6, VCPU_TFIAR(r9) - addi r1, r1, PPC_MIN_STKFRM + addi r1, r1, TM_FRAME_SIZE ld r0, PPC_LR_STKOFF(r1) mtlr r0 blr diff --git a/arch/powerpc/sysdev/xics/xics-common.c b/arch/powerpc/sysdev/xics/xics-common.c index 5c1a157a83b8..244a727c6ba4 100644 --- a/arch/powerpc/sysdev/xics/xics-common.c +++ b/arch/powerpc/sysdev/xics/xics-common.c @@ -348,9 +348,9 @@ static int xics_host_map(struct irq_domain *domain, unsigned int virq, if (xics_ics->check(xics_ics, hwirq)) return -EINVAL; - /* No chip data for the XICS domain */ + /* Let the ICS be the chip data for the XICS domain. For ICS native */ irq_domain_set_info(domain, virq, hwirq, xics_ics->chip, - NULL, handle_fasteoi_irq, NULL, NULL); + xics_ics, handle_fasteoi_irq, NULL, NULL); return 0; } diff --git a/tools/testing/selftests/powerpc/tm/tm-syscall-asm.S b/tools/testing/selftests/powerpc/tm/tm-syscall-asm.S index bd1ca25febe4..aed632d29fff 100644 --- a/tools/testing/selftests/powerpc/tm/tm-syscall-asm.S +++ b/tools/testing/selftests/powerpc/tm/tm-syscall-asm.S @@ -1,5 +1,5 @@ /* SPDX-License-Identifier: GPL-2.0 */ -#include <ppc-asm.h> +#include <basic_asm.h> #include <asm/unistd.h> .text @@ -26,3 +26,38 @@ FUNC_START(getppid_tm_suspended) 1: li r3, -1 blr + + +.macro scv level + .long (0x44000001 | (\level) << 5) +.endm + +FUNC_START(getppid_scv_tm_active) + PUSH_BASIC_STACK(0) + tbegin. + beq 1f + li r0, __NR_getppid + scv 0 + tend. + POP_BASIC_STACK(0) + blr +1: + li r3, -1 + POP_BASIC_STACK(0) + blr + +FUNC_START(getppid_scv_tm_suspended) + PUSH_BASIC_STACK(0) + tbegin. + beq 1f + li r0, __NR_getppid + tsuspend. + scv 0 + tresume. + tend. + POP_BASIC_STACK(0) + blr +1: + li r3, -1 + POP_BASIC_STACK(0) + blr diff --git a/tools/testing/selftests/powerpc/tm/tm-syscall.c b/tools/testing/selftests/powerpc/tm/tm-syscall.c index 467a6b3134b2..b763354c2eb4 100644 --- a/tools/testing/selftests/powerpc/tm/tm-syscall.c +++ b/tools/testing/selftests/powerpc/tm/tm-syscall.c @@ -19,23 +19,36 @@ #include "utils.h" #include "tm.h" +#ifndef PPC_FEATURE2_SCV +#define PPC_FEATURE2_SCV 0x00100000 /* scv syscall */ +#endif + extern int getppid_tm_active(void); extern int getppid_tm_suspended(void); +extern int getppid_scv_tm_active(void); +extern int getppid_scv_tm_suspended(void); unsigned retries = 0; #define TEST_DURATION 10 /* seconds */ -pid_t getppid_tm(bool suspend) +pid_t getppid_tm(bool scv, bool suspend) { int i; pid_t pid; for (i = 0; i < TM_RETRIES; i++) { - if (suspend) - pid = getppid_tm_suspended(); - else - pid = getppid_tm_active(); + if (suspend) { + if (scv) + pid = getppid_scv_tm_suspended(); + else + pid = getppid_tm_suspended(); + } else { + if (scv) + pid = getppid_scv_tm_active(); + else + pid = getppid_tm_active(); + } if (pid >= 0) return pid; @@ -82,15 +95,24 @@ int tm_syscall(void) * Test a syscall within a suspended transaction and verify * that it succeeds. */ - FAIL_IF(getppid_tm(true) == -1); /* Should succeed. */ + FAIL_IF(getppid_tm(false, true) == -1); /* Should succeed. */ /* * Test a syscall within an active transaction and verify that * it fails with the correct failure code. */ - FAIL_IF(getppid_tm(false) != -1); /* Should fail... */ + FAIL_IF(getppid_tm(false, false) != -1); /* Should fail... */ FAIL_IF(!failure_is_persistent()); /* ...persistently... */ FAIL_IF(!failure_is_syscall()); /* ...with code syscall. */ + + /* Now do it all again with scv if it is available. */ + if (have_hwcap2(PPC_FEATURE2_SCV)) { + FAIL_IF(getppid_tm(true, true) == -1); /* Should succeed. */ + FAIL_IF(getppid_tm(true, false) != -1); /* Should fail... */ + FAIL_IF(!failure_is_persistent()); /* ...persistently... */ + FAIL_IF(!failure_is_syscall()); /* ...with code syscall. */ + } + gettimeofday(&now, 0); } |