scftorture: Count single_rpc offline failures in statistics outputgrafted

scf_torture_stats_print() aggregates each invoker thread's counters
into a local scf_statistics structure before printing, but the
n_single_rpc_ofl field is missing from the aggregation loop.  As a
result, the "single_rpc_ofl" value printed in the statistics line is
always zero, even when smp_call_function_single() invocations for the
RPC test have failed due to offline CPUs and been counted by the
invoker threads.

Add the missing accumulation so that the printed value reflects the
actual counts.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

1 files changed, 178 insertions, 0 deletions

diff --git a/drivers/misc/lkdtm/powerpc.c b/drivers/misc/lkdtm/powerpc.c
new file mode 100644
index 000000000..6eaac79ea
--- /dev/null
+++ b/drivers/misc/lkdtm/powerpc.c
@@ -0,0 +1,178 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "lkdtm.h"
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <asm/mmu.h>
+
+#ifdef CONFIG_PPC_64S_HASH_MMU
+/* Inserts new slb entries */
+static void insert_slb_entry(unsigned long p, int ssize, int page_size)
+{
+	unsigned long flags;
+
+	flags = SLB_VSID_KERNEL | mmu_psize_defs[page_size].sllp;
+	preempt_disable();
+
+	asm volatile("slbmte %0,%1" :
+		     : "r" (mk_vsid_data(p, ssize, flags)),
+		       "r" (mk_esid_data(p, ssize, SLB_NUM_BOLTED))
+		     : "memory");
+	isync();
+
+	asm volatile("slbmte %0,%1" :
+			: "r" (mk_vsid_data(p, ssize, flags)),
+			  "r" (mk_esid_data(p, ssize, SLB_NUM_BOLTED + 1))
+			: "memory");
+	isync();
+
+	preempt_enable();
+}
+
+/* Inject slb multihit on vmalloc-ed address i.e 0xD00... */
+static int inject_vmalloc_slb_multihit(void)
+{
+	char *p;
+
+	p = vmalloc(PAGE_SIZE);
+	if (!p)
+		return -ENOMEM;
+
+	insert_slb_entry((unsigned long)p, MMU_SEGSIZE_1T, mmu_vmalloc_psize);
+	/*
+	 * This triggers exception, If handled correctly we must recover
+	 * from this error.
+	 */
+	p[0] = '!';
+	vfree(p);
+	return 0;
+}
+
+/* Inject slb multihit on kmalloc-ed address i.e 0xC00... */
+static int inject_kmalloc_slb_multihit(void)
+{
+	char *p;
+
+	p = kmalloc(2048, GFP_KERNEL);
+	if (!p)
+		return -ENOMEM;
+
+	insert_slb_entry((unsigned long)p, MMU_SEGSIZE_1T, mmu_linear_psize);
+	/*
+	 * This triggers exception, If handled correctly we must recover
+	 * from this error.
+	 */
+	p[0] = '!';
+	kfree(p);
+	return 0;
+}
+
+/*
+ * Few initial SLB entries are bolted. Add a test to inject
+ * multihit in bolted entry 0.
+ */
+static void insert_dup_slb_entry_0(void)
+{
+	unsigned long test_address = PAGE_OFFSET, *test_ptr;
+	unsigned long esid, vsid;
+	unsigned long i = 0;
+
+	test_ptr = (unsigned long *)test_address;
+	preempt_disable();
+
+	asm volatile("slbmfee  %0,%1" : "=r" (esid) : "r" (i));
+	asm volatile("slbmfev  %0,%1" : "=r" (vsid) : "r" (i));
+
+	/* for i !=0 we would need to mask out the old entry number */
+	asm volatile("slbmte %0,%1" :
+			: "r" (vsid),
+			  "r" (esid | SLB_NUM_BOLTED)
+			: "memory");
+	isync();
+
+	asm volatile("slbmfee  %0,%1" : "=r" (esid) : "r" (i));
+	asm volatile("slbmfev  %0,%1" : "=r" (vsid) : "r" (i));
+
+	/* for i !=0 we would need to mask out the old entry number */
+	asm volatile("slbmte %0,%1" :
+			: "r" (vsid),
+			  "r" (esid | (SLB_NUM_BOLTED + 1))
+			: "memory");
+	isync();
+
+	pr_info("%s accessing test address 0x%lx: 0x%lx\n",
+		__func__, test_address, *test_ptr);
+
+	preempt_enable();
+}
+#endif /* CONFIG_PPC_64S_HASH_MMU */
+
+static __always_inline void tlbiel_va(unsigned long va,
+				      unsigned long pid,
+				      unsigned long ap,
+				      unsigned long ric)
+{
+	unsigned long rb, rs, prs, r;
+
+	rb = va & ~(PPC_BITMASK(52, 63));
+	rb |= ap << PPC_BITLSHIFT(58);
+	rs = pid << PPC_BITLSHIFT(31);
+
+	prs = 1; /* process scoped */
+	r = 1;   /* radix format */
+
+	/*
+	 * Trigger an MCE by issuing radix tlbiel with an invalid operand combination.
+	 * The combination of RIC = 2 with IS = 0 (Invalidation selector specified
+	 * in the RB register) is invalid.
+	 * This invalid combination causes hardware to raise a machine check.
+	 */
+	asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
+			: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
+}
+
+static void lkdtm_PPC_SLB_MULTIHIT(void)
+{
+#ifdef CONFIG_PPC_64S_HASH_MMU
+	if (!radix_enabled()) {
+		pr_info("Injecting SLB multihit errors\n");
+		/*
+		 * These need not be separate tests, And they do pretty
+		 * much same thing. In any case we must recover from the
+		 * errors introduced by these functions, machine would not
+		 * survive these tests in case of failure to handle.
+		 */
+		inject_vmalloc_slb_multihit();
+		inject_kmalloc_slb_multihit();
+		insert_dup_slb_entry_0();
+		pr_info("Recovered from SLB multihit errors\n");
+	} else {
+		pr_err("XFAIL: This test is for ppc64 and with hash mode MMU only\n");
+	}
+#else
+	pr_err("XFAIL: This test requires CONFIG_PPC_64S_HASH_MMU\n");
+#endif
+}
+
+static void lkdtm_PPC_RADIX_TLBIEL(void)
+{
+	unsigned long addr = PAGE_OFFSET;
+
+	if (radix_enabled()) {
+		pr_info("Injecting Radix TLB invalidation MCE\n");
+		tlbiel_va(addr, 0, 0, RIC_FLUSH_ALL);
+		pr_info("Recovered from radix tlbiel attempt\n");
+	} else {
+		pr_err("XFAIL: This test is for ppc64 and with radix mode MMU only\n");
+	}
+}
+
+static struct crashtype crashtypes[] = {
+	CRASHTYPE(PPC_SLB_MULTIHIT),
+	CRASHTYPE(PPC_RADIX_TLBIEL),
+};
+
+struct crashtype_category powerpc_crashtypes = {
+	.crashtypes = crashtypes,
+	.len	    = ARRAY_SIZE(crashtypes),
+};