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authorLinus Torvalds <torvalds@linux-foundation.org>2017-11-16 12:47:46 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-11-16 12:47:46 -0800
commit5b0e2cb020085efe202123162502e0b551e49a0e (patch)
tree534bbb4c9f98c2ed9a520e11107029e5df38c3c2 /arch/powerpc/kernel/traps.c
parent758f875848d78148cf9a9cdb3ff1ddf29b234056 (diff)
parent3ffa9d9e2a7c10127d8cbf91ea2be15390b450ed (diff)
Merge tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman: "A bit of a small release, I suspect in part due to me travelling for KS. But my backlog of patches to review is smaller than usual, so I think in part folks just didn't send as much this cycle. Non-highlights: - Five fixes for the >128T address space handling, both to fix bugs in our implementation and to bring the semantics exactly into line with x86. Highlights: - Support for a new OPAL call on bare metal machines which gives us a true NMI (ie. is not masked by MSR[EE]=0) for debugging etc. - Support for Power9 DD2 in the CXL driver. - Improvements to machine check handling so that uncorrectable errors can be reported into the generic memory_failure() machinery. - Some fixes and improvements for VPHN, which is used under PowerVM to notify the Linux partition of topology changes. - Plumbing to enable TM (transactional memory) without suspend on some Power9 processors (PPC_FEATURE2_HTM_NO_SUSPEND). - Support for emulating vector loads form cache-inhibited memory, on some Power9 revisions. - Disable the fast-endian switch "syscall" by default (behind a CONFIG), we believe it has never had any users. - A major rework of the API drivers use when initiating and waiting for long running operations performed by OPAL firmware, and changes to the powernv_flash driver to use the new API. - Several fixes for the handling of FP/VMX/VSX while processes are using transactional memory. - Optimisations of TLB range flushes when using the radix MMU on Power9. - Improvements to the VAS facility used to access coprocessors on Power9, and related improvements to the way the NX crypto driver handles requests. - Implementation of PMEM_API and UACCESS_FLUSHCACHE for 64-bit. Thanks to: Alexey Kardashevskiy, Alistair Popple, Allen Pais, Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Balbir Singh, Benjamin Herrenschmidt, Breno Leitao, Christophe Leroy, Christophe Lombard, Cyril Bur, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Guilherme G. Piccoli, Gustavo Romero, Haren Myneni, Joel Stanley, Kamalesh Babulal, Kautuk Consul, Markus Elfring, Masami Hiramatsu, Michael Bringmann, Michael Neuling, Michal Suchanek, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pedro Miraglia Franco de Carvalho, Philippe Bergheaud, Sandipan Das, Seth Forshee, Shriya, Stephen Rothwell, Stewart Smith, Sukadev Bhattiprolu, Tyrel Datwyler, Vaibhav Jain, Vaidyanathan Srinivasan, and William A. Kennington III" * tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (151 commits) powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 feature powerpc/64s: Fix masking of SRR1 bits on instruction fault powerpc/64s: mm_context.addr_limit is only used on hash powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation powerpc/64s/hash: Allow MAP_FIXED allocations to cross 128TB boundary powerpc/64s/hash: Fix fork() with 512TB process address space powerpc/64s/hash: Fix 128TB-512TB virtual address boundary case allocation powerpc/64s/hash: Fix 512T hint detection to use >= 128T powerpc: Fix DABR match on hash based systems powerpc/signal: Properly handle return value from uprobe_deny_signal() powerpc/fadump: use kstrtoint to handle sysfs store powerpc/lib: Implement UACCESS_FLUSHCACHE API powerpc/lib: Implement PMEM API powerpc/powernv/npu: Don't explicitly flush nmmu tlb powerpc/powernv/npu: Use flush_all_mm() instead of flush_tlb_mm() powerpc/powernv/idle: Round up latency and residency values powerpc/kprobes: refactor kprobe_lookup_name for safer string operations powerpc/kprobes: Blacklist emulate_update_regs() from kprobes powerpc/kprobes: Do not disable interrupts for optprobes and kprobes_on_ftrace powerpc/kprobes: Disable preemption before invoking probe handler for optprobes ...
Diffstat (limited to 'arch/powerpc/kernel/traps.c')
-rw-r--r--arch/powerpc/kernel/traps.c256
1 files changed, 210 insertions, 46 deletions
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 13c9dcdcba69..f3eb61be0d30 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -37,6 +37,7 @@
#include <linux/kdebug.h>
#include <linux/ratelimit.h>
#include <linux/context_tracking.h>
+#include <linux/smp.h>
#include <asm/emulated_ops.h>
#include <asm/pgtable.h>
@@ -699,6 +700,187 @@ void SMIException(struct pt_regs *regs)
die("System Management Interrupt", regs, SIGABRT);
}
+#ifdef CONFIG_VSX
+static void p9_hmi_special_emu(struct pt_regs *regs)
+{
+ unsigned int ra, rb, t, i, sel, instr, rc;
+ const void __user *addr;
+ u8 vbuf[16], *vdst;
+ unsigned long ea, msr, msr_mask;
+ bool swap;
+
+ if (__get_user_inatomic(instr, (unsigned int __user *)regs->nip))
+ return;
+
+ /*
+ * lxvb16x opcode: 0x7c0006d8
+ * lxvd2x opcode: 0x7c000698
+ * lxvh8x opcode: 0x7c000658
+ * lxvw4x opcode: 0x7c000618
+ */
+ if ((instr & 0xfc00073e) != 0x7c000618) {
+ pr_devel("HMI vec emu: not vector CI %i:%s[%d] nip=%016lx"
+ " instr=%08x\n",
+ smp_processor_id(), current->comm, current->pid,
+ regs->nip, instr);
+ return;
+ }
+
+ /* Grab vector registers into the task struct */
+ msr = regs->msr; /* Grab msr before we flush the bits */
+ flush_vsx_to_thread(current);
+ enable_kernel_altivec();
+
+ /*
+ * Is userspace running with a different endian (this is rare but
+ * not impossible)
+ */
+ swap = (msr & MSR_LE) != (MSR_KERNEL & MSR_LE);
+
+ /* Decode the instruction */
+ ra = (instr >> 16) & 0x1f;
+ rb = (instr >> 11) & 0x1f;
+ t = (instr >> 21) & 0x1f;
+ if (instr & 1)
+ vdst = (u8 *)&current->thread.vr_state.vr[t];
+ else
+ vdst = (u8 *)&current->thread.fp_state.fpr[t][0];
+
+ /* Grab the vector address */
+ ea = regs->gpr[rb] + (ra ? regs->gpr[ra] : 0);
+ if (is_32bit_task())
+ ea &= 0xfffffffful;
+ addr = (__force const void __user *)ea;
+
+ /* Check it */
+ if (!access_ok(VERIFY_READ, addr, 16)) {
+ pr_devel("HMI vec emu: bad access %i:%s[%d] nip=%016lx"
+ " instr=%08x addr=%016lx\n",
+ smp_processor_id(), current->comm, current->pid,
+ regs->nip, instr, (unsigned long)addr);
+ return;
+ }
+
+ /* Read the vector */
+ rc = 0;
+ if ((unsigned long)addr & 0xfUL)
+ /* unaligned case */
+ rc = __copy_from_user_inatomic(vbuf, addr, 16);
+ else
+ __get_user_atomic_128_aligned(vbuf, addr, rc);
+ if (rc) {
+ pr_devel("HMI vec emu: page fault %i:%s[%d] nip=%016lx"
+ " instr=%08x addr=%016lx\n",
+ smp_processor_id(), current->comm, current->pid,
+ regs->nip, instr, (unsigned long)addr);
+ return;
+ }
+
+ pr_devel("HMI vec emu: emulated vector CI %i:%s[%d] nip=%016lx"
+ " instr=%08x addr=%016lx\n",
+ smp_processor_id(), current->comm, current->pid, regs->nip,
+ instr, (unsigned long) addr);
+
+ /* Grab instruction "selector" */
+ sel = (instr >> 6) & 3;
+
+ /*
+ * Check to make sure the facility is actually enabled. This
+ * could happen if we get a false positive hit.
+ *
+ * lxvd2x/lxvw4x always check MSR VSX sel = 0,2
+ * lxvh8x/lxvb16x check MSR VSX or VEC depending on VSR used sel = 1,3
+ */
+ msr_mask = MSR_VSX;
+ if ((sel & 1) && (instr & 1)) /* lxvh8x & lxvb16x + VSR >= 32 */
+ msr_mask = MSR_VEC;
+ if (!(msr & msr_mask)) {
+ pr_devel("HMI vec emu: MSR fac clear %i:%s[%d] nip=%016lx"
+ " instr=%08x msr:%016lx\n",
+ smp_processor_id(), current->comm, current->pid,
+ regs->nip, instr, msr);
+ return;
+ }
+
+ /* Do logging here before we modify sel based on endian */
+ switch (sel) {
+ case 0: /* lxvw4x */
+ PPC_WARN_EMULATED(lxvw4x, regs);
+ break;
+ case 1: /* lxvh8x */
+ PPC_WARN_EMULATED(lxvh8x, regs);
+ break;
+ case 2: /* lxvd2x */
+ PPC_WARN_EMULATED(lxvd2x, regs);
+ break;
+ case 3: /* lxvb16x */
+ PPC_WARN_EMULATED(lxvb16x, regs);
+ break;
+ }
+
+#ifdef __LITTLE_ENDIAN__
+ /*
+ * An LE kernel stores the vector in the task struct as an LE
+ * byte array (effectively swapping both the components and
+ * the content of the components). Those instructions expect
+ * the components to remain in ascending address order, so we
+ * swap them back.
+ *
+ * If we are running a BE user space, the expectation is that
+ * of a simple memcpy, so forcing the emulation to look like
+ * a lxvb16x should do the trick.
+ */
+ if (swap)
+ sel = 3;
+
+ switch (sel) {
+ case 0: /* lxvw4x */
+ for (i = 0; i < 4; i++)
+ ((u32 *)vdst)[i] = ((u32 *)vbuf)[3-i];
+ break;
+ case 1: /* lxvh8x */
+ for (i = 0; i < 8; i++)
+ ((u16 *)vdst)[i] = ((u16 *)vbuf)[7-i];
+ break;
+ case 2: /* lxvd2x */
+ for (i = 0; i < 2; i++)
+ ((u64 *)vdst)[i] = ((u64 *)vbuf)[1-i];
+ break;
+ case 3: /* lxvb16x */
+ for (i = 0; i < 16; i++)
+ vdst[i] = vbuf[15-i];
+ break;
+ }
+#else /* __LITTLE_ENDIAN__ */
+ /* On a big endian kernel, a BE userspace only needs a memcpy */
+ if (!swap)
+ sel = 3;
+
+ /* Otherwise, we need to swap the content of the components */
+ switch (sel) {
+ case 0: /* lxvw4x */
+ for (i = 0; i < 4; i++)
+ ((u32 *)vdst)[i] = cpu_to_le32(((u32 *)vbuf)[i]);
+ break;
+ case 1: /* lxvh8x */
+ for (i = 0; i < 8; i++)
+ ((u16 *)vdst)[i] = cpu_to_le16(((u16 *)vbuf)[i]);
+ break;
+ case 2: /* lxvd2x */
+ for (i = 0; i < 2; i++)
+ ((u64 *)vdst)[i] = cpu_to_le64(((u64 *)vbuf)[i]);
+ break;
+ case 3: /* lxvb16x */
+ memcpy(vdst, vbuf, 16);
+ break;
+ }
+#endif /* !__LITTLE_ENDIAN__ */
+
+ /* Go to next instruction */
+ regs->nip += 4;
+}
+#endif /* CONFIG_VSX */
+
void handle_hmi_exception(struct pt_regs *regs)
{
struct pt_regs *old_regs;
@@ -706,6 +888,21 @@ void handle_hmi_exception(struct pt_regs *regs)
old_regs = set_irq_regs(regs);
irq_enter();
+#ifdef CONFIG_VSX
+ /* Real mode flagged P9 special emu is needed */
+ if (local_paca->hmi_p9_special_emu) {
+ local_paca->hmi_p9_special_emu = 0;
+
+ /*
+ * We don't want to take page faults while doing the
+ * emulation, we just replay the instruction if necessary.
+ */
+ pagefault_disable();
+ p9_hmi_special_emu(regs);
+ pagefault_enable();
+ }
+#endif /* CONFIG_VSX */
+
if (ppc_md.handle_hmi_exception)
ppc_md.handle_hmi_exception(regs);
@@ -1140,13 +1337,8 @@ void program_check_exception(struct pt_regs *regs)
* - A treclaim is attempted when non transactional.
* - A tend is illegally attempted.
* - writing a TM SPR when transactional.
- */
- if (!user_mode(regs) &&
- report_bug(regs->nip, regs) == BUG_TRAP_TYPE_WARN) {
- regs->nip += 4;
- goto bail;
- }
- /* If usermode caused this, it's done something illegal and
+ *
+ * If usermode caused this, it's done something illegal and
* gets a SIGILL slap on the wrist. We call it an illegal
* operand to distinguish from the instruction just being bad
* (e.g. executing a 'tend' on a CPU without TM!); it's an
@@ -1487,7 +1679,7 @@ void fp_unavailable_tm(struct pt_regs *regs)
/* Reclaim didn't save out any FPRs to transact_fprs. */
/* Enable FP for the task: */
- regs->msr |= (MSR_FP | current->thread.fpexc_mode);
+ current->thread.load_fp = 1;
/* This loads and recheckpoints the FP registers from
* thread.fpr[]. They will remain in registers after the
@@ -1495,15 +1687,7 @@ void fp_unavailable_tm(struct pt_regs *regs)
* If VMX is in use, the VRs now hold checkpointed values,
* so we don't want to load the VRs from the thread_struct.
*/
- tm_recheckpoint(&current->thread, MSR_FP);
-
- /* If VMX is in use, get the transactional values back */
- if (regs->msr & MSR_VEC) {
- msr_check_and_set(MSR_VEC);
- load_vr_state(&current->thread.vr_state);
- /* At this point all the VSX state is loaded, so enable it */
- regs->msr |= MSR_VSX;
- }
+ tm_recheckpoint(&current->thread);
}
void altivec_unavailable_tm(struct pt_regs *regs)
@@ -1516,21 +1700,13 @@ void altivec_unavailable_tm(struct pt_regs *regs)
"MSR=%lx\n",
regs->nip, regs->msr);
tm_reclaim_current(TM_CAUSE_FAC_UNAV);
- regs->msr |= MSR_VEC;
- tm_recheckpoint(&current->thread, MSR_VEC);
+ current->thread.load_vec = 1;
+ tm_recheckpoint(&current->thread);
current->thread.used_vr = 1;
-
- if (regs->msr & MSR_FP) {
- msr_check_and_set(MSR_FP);
- load_fp_state(&current->thread.fp_state);
- regs->msr |= MSR_VSX;
- }
}
void vsx_unavailable_tm(struct pt_regs *regs)
{
- unsigned long orig_msr = regs->msr;
-
/* See the comments in fp_unavailable_tm(). This works similarly,
* though we're loading both FP and VEC registers in here.
*
@@ -1544,29 +1720,13 @@ void vsx_unavailable_tm(struct pt_regs *regs)
current->thread.used_vsr = 1;
- /* If FP and VMX are already loaded, we have all the state we need */
- if ((orig_msr & (MSR_FP | MSR_VEC)) == (MSR_FP | MSR_VEC)) {
- regs->msr |= MSR_VSX;
- return;
- }
-
/* This reclaims FP and/or VR regs if they're already enabled */
tm_reclaim_current(TM_CAUSE_FAC_UNAV);
- regs->msr |= MSR_VEC | MSR_FP | current->thread.fpexc_mode |
- MSR_VSX;
-
- /* This loads & recheckpoints FP and VRs; but we have
- * to be sure not to overwrite previously-valid state.
- */
- tm_recheckpoint(&current->thread, regs->msr & ~orig_msr);
-
- msr_check_and_set(orig_msr & (MSR_FP | MSR_VEC));
+ current->thread.load_vec = 1;
+ current->thread.load_fp = 1;
- if (orig_msr & MSR_FP)
- load_fp_state(&current->thread.fp_state);
- if (orig_msr & MSR_VEC)
- load_vr_state(&current->thread.vr_state);
+ tm_recheckpoint(&current->thread);
}
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
@@ -1924,6 +2084,10 @@ struct ppc_emulated ppc_emulated = {
WARN_EMULATED_SETUP(mfdscr),
WARN_EMULATED_SETUP(mtdscr),
WARN_EMULATED_SETUP(lq_stq),
+ WARN_EMULATED_SETUP(lxvw4x),
+ WARN_EMULATED_SETUP(lxvh8x),
+ WARN_EMULATED_SETUP(lxvd2x),
+ WARN_EMULATED_SETUP(lxvb16x),
#endif
};