Merge tag 's390-5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/g…

…it/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add support for KASAN_VMALLOC feature.

 - Remove the last user of problematic diag 0x44 call.

 - Adjust sampling interval and avoid sample data block overflow
   condition on pressure in perf code.

 - Prefer EOPNOTSUPP over ENOTSUPP and comments fixes.

* tag 's390-5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/kasan: add KASAN_VMALLOC support
  s390: remove last diag 0x44 caller
  s390/uv: use EOPNOTSUPP instead of ENOTSUPP
  s390/cpum_sf: Avoid SBD overflow condition in irq handler
  s390/cpum_sf: Adjust sampling interval to avoid hitting sample limits
  s390/test_unwind: fix spelling mistake "reqister" -> "register"
  s390/spinlock: remove confusing comment in arch_spin_lock_wait

arch/s390/Kconfig

@@ -124,6 +124,7 @@ config S390
 	select HAVE_ARCH_JUMP_LABEL
 	select HAVE_ARCH_JUMP_LABEL_RELATIVE
 	select HAVE_ARCH_KASAN
+	select HAVE_ARCH_KASAN_VMALLOC
 	select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES
 	select HAVE_ARCH_SECCOMP_FILTER
 	select HAVE_ARCH_SOFT_DIRTY

arch/s390/include/asm/setup.h

@@ -27,7 +27,6 @@
 #define MACHINE_FLAG_DIAG9C	BIT(3)
 #define MACHINE_FLAG_ESOP	BIT(4)
 #define MACHINE_FLAG_IDTE	BIT(5)
-#define MACHINE_FLAG_DIAG44	BIT(6)
 #define MACHINE_FLAG_EDAT1	BIT(7)
 #define MACHINE_FLAG_EDAT2	BIT(8)
 #define MACHINE_FLAG_TOPOLOGY	BIT(10)
@@ -94,7 +93,6 @@ extern unsigned long __swsusp_reset_dma;
 #define MACHINE_HAS_DIAG9C	(S390_lowcore.machine_flags & MACHINE_FLAG_DIAG9C)
 #define MACHINE_HAS_ESOP	(S390_lowcore.machine_flags & MACHINE_FLAG_ESOP)
 #define MACHINE_HAS_IDTE	(S390_lowcore.machine_flags & MACHINE_FLAG_IDTE)
-#define MACHINE_HAS_DIAG44	(S390_lowcore.machine_flags & MACHINE_FLAG_DIAG44)
 #define MACHINE_HAS_EDAT1	(S390_lowcore.machine_flags & MACHINE_FLAG_EDAT1)
 #define MACHINE_HAS_EDAT2	(S390_lowcore.machine_flags & MACHINE_FLAG_EDAT2)
 #define MACHINE_HAS_TOPOLOGY	(S390_lowcore.machine_flags & MACHINE_FLAG_TOPOLOGY)

arch/s390/include/asm/uv.h

@@ -86,7 +86,7 @@ static inline int share(unsigned long addr, u16 cmd)
 	};
 
 	if (!is_prot_virt_guest())
-		return -ENOTSUPP;
+		return -EOPNOTSUPP;
 	/*
 	 * Sharing is page wise, if we encounter addresses that are
 	 * not page aligned, we assume something went wrong. If

arch/s390/kernel/early.c

@@ -204,21 +204,6 @@ static __init void detect_diag9c(void)
 		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
 }
 
-static __init void detect_diag44(void)
-{
-	int rc;
-
-	diag_stat_inc(DIAG_STAT_X044);
-	asm volatile(
-		"	diag	0,0,0x44\n"
-		"0:	la	%0,0\n"
-		"1:\n"
-		EX_TABLE(0b,1b)
-		: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
-	if (!rc)
-		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
-}
-
 static __init void detect_machine_facilities(void)
 {
 	if (test_facility(8)) {
@@ -331,7 +316,6 @@ void __init startup_init(void)
 	setup_arch_string();
 	setup_boot_command_line();
 	detect_diag9c();
-	detect_diag44();
 	detect_machine_facilities();
 	save_vector_registers();
 	setup_topology();

arch/s390/kernel/perf_cpum_sf.c

@@ -1303,18 +1303,28 @@ static void hw_perf_event_update(struct perf_event *event, int flush_all)
 		 */
 		if (flush_all && done)
 			break;
-
-		/* If an event overflow happened, discard samples by
-		 * processing any remaining sample-data-blocks.
-		 */
-		if (event_overflow)
-			flush_all = 1;
 	}
 
 	/* Account sample overflows in the event hardware structure */
 	if (sampl_overflow)
 		OVERFLOW_REG(hwc) = DIV_ROUND_UP(OVERFLOW_REG(hwc) +
 						 sampl_overflow, 1 + num_sdb);
+
+	/* Perf_event_overflow() and perf_event_account_interrupt() limit
+	 * the interrupt rate to an upper limit. Roughly 1000 samples per
+	 * task tick.
+	 * Hitting this limit results in a large number
+	 * of throttled REF_REPORT_THROTTLE entries and the samples
+	 * are dropped.
+	 * Slightly increase the interval to avoid hitting this limit.
+	 */
+	if (event_overflow) {
+		SAMPL_RATE(hwc) += DIV_ROUND_UP(SAMPL_RATE(hwc), 10);
+		debug_sprintf_event(sfdbg, 1, "%s: rate adjustment %ld\n",
+				    __func__,
+				    DIV_ROUND_UP(SAMPL_RATE(hwc), 10));
+	}
+
 	if (sampl_overflow || event_overflow)
 		debug_sprintf_event(sfdbg, 4, "%s: "
 				    "overflows: sample %llu event %llu"

arch/s390/kernel/smp.c

@@ -413,14 +413,11 @@ EXPORT_SYMBOL(arch_vcpu_is_preempted);
 
 void smp_yield_cpu(int cpu)
 {
-	if (MACHINE_HAS_DIAG9C) {
-		diag_stat_inc_norecursion(DIAG_STAT_X09C);
-		asm volatile("diag %0,0,0x9c"
-			     : : "d" (pcpu_devices[cpu].address));
-	} else if (MACHINE_HAS_DIAG44 && !smp_cpu_mtid) {
-		diag_stat_inc_norecursion(DIAG_STAT_X044);
-		asm volatile("diag 0,0,0x44");
-	}
+	if (!MACHINE_HAS_DIAG9C)
+		return;
+	diag_stat_inc_norecursion(DIAG_STAT_X09C);
+	asm volatile("diag %0,0,0x9c"
+		     : : "d" (pcpu_devices[cpu].address));
 }
 
 /*

arch/s390/lib/spinlock.c

@@ -242,7 +242,6 @@ static inline void arch_spin_lock_classic(arch_spinlock_t *lp)
 
 void arch_spin_lock_wait(arch_spinlock_t *lp)
 {
-	/* Use classic spinlocks + niai if the steal time is >= 10% */
 	if (test_cpu_flag(CIF_DEDICATED_CPU))
 		arch_spin_lock_queued(lp);
 	else

arch/s390/lib/test_unwind.c

@@ -238,7 +238,7 @@ static int test_unwind_irq(struct unwindme *u)
 {
 	preempt_disable();
 	if (register_external_irq(EXT_IRQ_CLK_COMP, unwindme_irq_handler)) {
-		pr_info("Couldn't reqister external interrupt handler");
+		pr_info("Couldn't register external interrupt handler");
 		return -1;
 	}
 	u->task = current;

arch/s390/mm/kasan_init.c

@@ -82,7 +82,8 @@ static pte_t * __init kasan_early_pte_alloc(void)
 enum populate_mode {
 	POPULATE_ONE2ONE,
 	POPULATE_MAP,
-	POPULATE_ZERO_SHADOW
+	POPULATE_ZERO_SHADOW,
+	POPULATE_SHALLOW
 };
 static void __init kasan_early_vmemmap_populate(unsigned long address,
 						unsigned long end,
@@ -116,6 +117,12 @@ static void __init kasan_early_vmemmap_populate(unsigned long address,
 			pgd_populate(&init_mm, pg_dir, p4_dir);
 		}
 
+		if (IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING) &&
+		    mode == POPULATE_SHALLOW) {
+			address = (address + P4D_SIZE) & P4D_MASK;
+			continue;
+		}
+
 		p4_dir = p4d_offset(pg_dir, address);
 		if (p4d_none(*p4_dir)) {
 			if (mode == POPULATE_ZERO_SHADOW &&
@@ -130,6 +137,12 @@ static void __init kasan_early_vmemmap_populate(unsigned long address,
 			p4d_populate(&init_mm, p4_dir, pu_dir);
 		}
 
+		if (!IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING) &&
+		    mode == POPULATE_SHALLOW) {
+			address = (address + PUD_SIZE) & PUD_MASK;
+			continue;
+		}
+
 		pu_dir = pud_offset(p4_dir, address);
 		if (pud_none(*pu_dir)) {
 			if (mode == POPULATE_ZERO_SHADOW &&
@@ -195,6 +208,9 @@ static void __init kasan_early_vmemmap_populate(unsigned long address,
 				page = kasan_early_shadow_page;
 				pte_val(*pt_dir) = __pa(page) | pgt_prot_zero;
 				break;
+			case POPULATE_SHALLOW:
+				/* should never happen */
+				break;
 			}
 		}
 		address += PAGE_SIZE;
@@ -313,22 +329,50 @@ void __init kasan_early_init(void)
 	init_mm.pgd = early_pg_dir;
 	/*
 	 * Current memory layout:
-	 * +- 0 -------------+	 +- shadow start -+
-	 * | 1:1 ram mapping |	/| 1/8 ram	  |
-	 * +- end of ram ----+ / +----------------+
-	 * | ... gap ...     |/  |	kasan	  |
-	 * +- shadow start --+	 |	zero	  |
-	 * | 1/8 addr space  |	 |	page	  |
-	 * +- shadow end    -+	 |	mapping	  |
-	 * | ... gap ...     |\  |    (untracked) |
-	 * +- modules vaddr -+ \ +----------------+
-	 * | 2Gb	     |	\|	unmapped  | allocated per module
-	 * +-----------------+	 +- shadow end ---+
+	 * +- 0 -------------+	   +- shadow start -+
+	 * | 1:1 ram mapping |	  /| 1/8 ram	    |
+	 * |		     |	 / |		    |
+	 * +- end of ram ----+	/  +----------------+
+	 * | ... gap ...     | /   |		    |
+	 * |		     |/    |	kasan	    |
+	 * +- shadow start --+	   |	zero	    |
+	 * | 1/8 addr space  |	   |	page	    |
+	 * +- shadow end    -+	   |	mapping	    |
+	 * | ... gap ...     |\    |  (untracked)   |
+	 * +- vmalloc area  -+ \   |		    |
+	 * | vmalloc_size    |	\  |		    |
+	 * +- modules vaddr -+	 \ +----------------+
+	 * | 2Gb	     |	  \|	  unmapped  | allocated per module
+	 * +-----------------+	   +- shadow end ---+
+	 *
+	 * Current memory layout (KASAN_VMALLOC):
+	 * +- 0 -------------+	   +- shadow start -+
+	 * | 1:1 ram mapping |	  /| 1/8 ram	    |
+	 * |		     |	 / |		    |
+	 * +- end of ram ----+	/  +----------------+
+	 * | ... gap ...     | /   |	kasan	    |
+	 * |		     |/    |	zero	    |
+	 * +- shadow start --+	   |	page	    |
+	 * | 1/8 addr space  |	   |	mapping     |
+	 * +- shadow end    -+	   |  (untracked)   |
+	 * | ... gap ...     |\    |		    |
+	 * +- vmalloc area  -+ \   +- vmalloc area -+
+	 * | vmalloc_size    |	\  |shallow populate|
+	 * +- modules vaddr -+	 \ +- modules area -+
+	 * | 2Gb	     |	  \|shallow populate|
+	 * +-----------------+	   +- shadow end ---+
 	 */
 	/* populate kasan shadow (for identity mapping and zero page mapping) */
 	kasan_early_vmemmap_populate(__sha(0), __sha(memsize), POPULATE_MAP);
 	if (IS_ENABLED(CONFIG_MODULES))
 		untracked_mem_end = vmax - MODULES_LEN;
+	if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
+		untracked_mem_end = vmax - vmalloc_size - MODULES_LEN;
+		/* shallowly populate kasan shadow for vmalloc and modules */
+		kasan_early_vmemmap_populate(__sha(untracked_mem_end),
+					     __sha(vmax), POPULATE_SHALLOW);
+	}
+	/* populate kasan shadow for untracked memory */
 	kasan_early_vmemmap_populate(__sha(max_physmem_end),
 				     __sha(untracked_mem_end),
 				     POPULATE_ZERO_SHADOW);