From 800252976be89611ef86d6d04442a821018ed949 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Mon, 14 Nov 2011 11:18:59 +0100
Subject: [S390] wire up process_vm syscalls

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/include/asm/unistd.h    |  4 +++-
 arch/s390/kernel/compat_wrapper.S | 20 ++++++++++++++++++++
 arch/s390/kernel/syscalls.S       |  2 ++
 3 files changed, 25 insertions(+), 1 deletion(-)

(limited to 'arch/s390')

diff --git a/arch/s390/include/asm/unistd.h b/arch/s390/include/asm/unistd.h
index 404bdb9671b4..58de4c91c333 100644
--- a/arch/s390/include/asm/unistd.h
+++ b/arch/s390/include/asm/unistd.h
@@ -277,7 +277,9 @@
 #define __NR_clock_adjtime	337
 #define __NR_syncfs		338
 #define __NR_setns		339
-#define NR_syscalls 340
+#define __NR_process_vm_readv	340
+#define __NR_process_vm_writev	341
+#define NR_syscalls 342
 
 /* 
  * There are some system calls that are not present on 64 bit, some
diff --git a/arch/s390/kernel/compat_wrapper.S b/arch/s390/kernel/compat_wrapper.S
index 5006a1d9f5d0..18c51df9fe06 100644
--- a/arch/s390/kernel/compat_wrapper.S
+++ b/arch/s390/kernel/compat_wrapper.S
@@ -1627,3 +1627,23 @@ ENTRY(sys_setns_wrapper)
 	lgfr	%r2,%r2			# int
 	lgfr	%r3,%r3			# int
 	jg	sys_setns
+
+ENTRY(compat_sys_process_vm_readv_wrapper)
+	lgfr	%r2,%r2			# compat_pid_t
+	llgtr	%r3,%r3			# struct compat_iovec __user *
+	llgfr	%r4,%r4			# unsigned long
+	llgtr	%r5,%r5			# struct compat_iovec __user *
+	llgfr	%r6,%r6			# unsigned long
+	llgf	%r0,164(%r15)		# unsigned long
+	stg	%r0,160(%r15)
+	jg	sys_process_vm_readv
+
+ENTRY(compat_sys_process_vm_writev_wrapper)
+	lgfr	%r2,%r2			# compat_pid_t
+	llgtr	%r3,%r3			# struct compat_iovec __user *
+	llgfr	%r4,%r4			# unsigned long
+	llgtr	%r5,%r5			# struct compat_iovec __user *
+	llgfr	%r6,%r6			# unsigned long
+	llgf	%r0,164(%r15)		# unsigned long
+	stg	%r0,160(%r15)
+	jg	sys_process_vm_writev
diff --git a/arch/s390/kernel/syscalls.S b/arch/s390/kernel/syscalls.S
index 73eb08c874fb..bcab2f04ba58 100644
--- a/arch/s390/kernel/syscalls.S
+++ b/arch/s390/kernel/syscalls.S
@@ -348,3 +348,5 @@ SYSCALL(sys_open_by_handle_at,sys_open_by_handle_at,compat_sys_open_by_handle_at
 SYSCALL(sys_clock_adjtime,sys_clock_adjtime,compat_sys_clock_adjtime_wrapper)
 SYSCALL(sys_syncfs,sys_syncfs,sys_syncfs_wrapper)
 SYSCALL(sys_setns,sys_setns,sys_setns_wrapper)
+SYSCALL(sys_process_vm_readv,sys_process_vm_readv,compat_sys_process_vm_readv_wrapper) /* 340 */
+SYSCALL(sys_process_vm_writev,sys_process_vm_writev,compat_sys_process_vm_writev_wrapper)
-- 
cgit v1.2.3


From 09b538833b85521d937a06faf61e6a3273253cc0 Mon Sep 17 00:00:00 2001
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Date: Mon, 14 Nov 2011 11:19:00 +0100
Subject: [S390] fix pgste update logic

The pgste_update_all / pgste_update_young and pgste_set_pte need to
check if the pte entry contains a valid page address before the storage
key can be accessed. In addition pgste_set_pte needs to set the access
key and fetch protection bit of the new pte entry, not the old entry.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/include/asm/pgtable.h | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

(limited to 'arch/s390')

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 34ede0ea85a9..524d23b8610c 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -593,6 +593,8 @@ static inline pgste_t pgste_update_all(pte_t *ptep, pgste_t pgste)
 	unsigned long address, bits;
 	unsigned char skey;
 
+	if (!pte_present(*ptep))
+		return pgste;
 	address = pte_val(*ptep) & PAGE_MASK;
 	skey = page_get_storage_key(address);
 	bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
@@ -625,6 +627,8 @@ static inline pgste_t pgste_update_young(pte_t *ptep, pgste_t pgste)
 #ifdef CONFIG_PGSTE
 	int young;
 
+	if (!pte_present(*ptep))
+		return pgste;
 	young = page_reset_referenced(pte_val(*ptep) & PAGE_MASK);
 	/* Transfer page referenced bit to pte software bit (host view) */
 	if (young || (pgste_val(pgste) & RCP_HR_BIT))
@@ -638,13 +642,15 @@ static inline pgste_t pgste_update_young(pte_t *ptep, pgste_t pgste)
 
 }
 
-static inline void pgste_set_pte(pte_t *ptep, pgste_t pgste)
+static inline void pgste_set_pte(pte_t *ptep, pgste_t pgste, pte_t entry)
 {
 #ifdef CONFIG_PGSTE
 	unsigned long address;
 	unsigned long okey, nkey;
 
-	address = pte_val(*ptep) & PAGE_MASK;
+	if (!pte_present(entry))
+		return;
+	address = pte_val(entry) & PAGE_MASK;
 	okey = nkey = page_get_storage_key(address);
 	nkey &= ~(_PAGE_ACC_BITS | _PAGE_FP_BIT);
 	/* Set page access key and fetch protection bit from pgste */
@@ -712,7 +718,7 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 
 	if (mm_has_pgste(mm)) {
 		pgste = pgste_get_lock(ptep);
-		pgste_set_pte(ptep, pgste);
+		pgste_set_pte(ptep, pgste, entry);
 		*ptep = entry;
 		pgste_set_unlock(ptep, pgste);
 	} else
-- 
cgit v1.2.3


From fa2fb2f4a599c402bb2670dde27867dbbb7e3c45 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Mon, 14 Nov 2011 11:19:01 +0100
Subject: [S390] pfault: ignore leftover completion interrupts

Ignore completion interrupts if the initial interrupt hasn't been
received and the addressed task is not running. This case can only
happen if leftover (pending) completion interrupt gets delivered
which wasn't removed with the PFAULT CANCEL operation during cpu
hotplug.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/mm/fault.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

(limited to 'arch/s390')

diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 1766def5bc3f..a9a301866b3c 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -587,8 +587,13 @@ static void pfault_interrupt(unsigned int ext_int_code,
 		} else {
 			/* Completion interrupt was faster than initial
 			 * interrupt. Set pfault_wait to -1 so the initial
-			 * interrupt doesn't put the task to sleep. */
-			tsk->thread.pfault_wait = -1;
+			 * interrupt doesn't put the task to sleep.
+			 * If the task is not running, ignore the completion
+			 * interrupt since it must be a leftover of a PFAULT
+			 * CANCEL operation which didn't remove all pending
+			 * completion interrupts. */
+			if (tsk->state == TASK_RUNNING)
+				tsk->thread.pfault_wait = -1;
 		}
 		put_task_struct(tsk);
 	} else {
-- 
cgit v1.2.3


From 7a2512b744e72377c3fa5976f06a3f343e155d1f Mon Sep 17 00:00:00 2001
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Date: Mon, 14 Nov 2011 11:19:02 +0100
Subject: [S390] incorrect note program header

'readelf -n' on the s390 vmlinux file generates lots of warnings about
corrupt notes. The reason is that the 'NOTE' program header has incorrect
file and memory sizes. The problem is that the section following the
NOTES section do not switch to a different phdr and they get added to
the NOTE program section. Add a dummy entry to the linker script that
switches to the data phdr before the start of the RODATA section.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/kernel/vmlinux.lds.S | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'arch/s390')

diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index 56fe6bc81fee..e4c79ebb40e6 100644
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -43,6 +43,8 @@ SECTIONS
 
 	NOTES :text :note
 
+	.dummy : { *(.dummy) } :data
+
 	RODATA
 
 #ifdef CONFIG_SHARED_KERNEL
-- 
cgit v1.2.3


From 96603b505cb6c54782a27599afef65cc108ef5f2 Mon Sep 17 00:00:00 2001
From: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Date: Mon, 14 Nov 2011 11:19:03 +0100
Subject: [S390] Kconfig: Select CONFIG_KEXEC for CONFIG_CRASH_DUMP

The kdump infrastructure is built on top of kexec. Therefore
CONFIG_KEXEC has to be enabled when CONFIG_CRASH_DUMP is selected.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/Kconfig | 1 +
 1 file changed, 1 insertion(+)

(limited to 'arch/s390')

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index a9fbd43395f7..373679b3744a 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -572,6 +572,7 @@ config KEXEC
 config CRASH_DUMP
 	bool "kernel crash dumps"
 	depends on 64BIT
+	select KEXEC
 	help
 	  Generate crash dump after being started by kexec.
 	  Crash dump kernels are loaded in the main kernel with kexec-tools
-- 
cgit v1.2.3


From 3f25dc4fcbc371f86a61a6af759003ebd4965908 Mon Sep 17 00:00:00 2001
From: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Date: Mon, 14 Nov 2011 11:19:05 +0100
Subject: [S390] zfcpdump: Do not initialize zfcpdump in kdump mode

When the kernel is started in kdump mode, zfcpdump should not be
initialized because both dump methods can't be used at the same time.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/kernel/setup.c  | 4 +++-
 drivers/s390/char/zcore.c | 2 ++
 2 files changed, 5 insertions(+), 1 deletion(-)

(limited to 'arch/s390')

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 8ac6bfa2786c..e58a462949b1 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -211,6 +211,8 @@ static void __init setup_zfcpdump(unsigned int console_devno)
 
 	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 		return;
+	if (OLDMEM_BASE)
+		return;
 	if (console_devno != -1)
 		sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
 			ipl_info.data.fcp.dev_id.devno, console_devno);
@@ -482,7 +484,7 @@ static void __init setup_memory_end(void)
 
 
 #ifdef CONFIG_ZFCPDUMP
-	if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
+	if (ipl_info.type == IPL_TYPE_FCP_DUMP && !OLDMEM_BASE) {
 		memory_end = ZFCPDUMP_HSA_SIZE;
 		memory_end_set = 1;
 	}
diff --git a/drivers/s390/char/zcore.c b/drivers/s390/char/zcore.c
index 43068fbd0baa..1b6d9247fdc7 100644
--- a/drivers/s390/char/zcore.c
+++ b/drivers/s390/char/zcore.c
@@ -641,6 +641,8 @@ static int __init zcore_init(void)
 
 	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 		return -ENODATA;
+	if (OLDMEM_BASE)
+		return -ENODATA;
 
 	zcore_dbf = debug_register("zcore", 4, 1, 4 * sizeof(long));
 	debug_register_view(zcore_dbf, &debug_sprintf_view);
-- 
cgit v1.2.3


From cfa1e7e1d49c6f5f0b00b2cb890b521e5c0dc7ea Mon Sep 17 00:00:00 2001
From: Jan Glauber <jang@linux.vnet.ibm.com>
Date: Mon, 14 Nov 2011 11:19:06 +0100
Subject: [S390] avoid STCKF if running in ESA mode

In ESA mode STCKF is not defined even if the facility bit is enabled.
To prevent an illegal operation we must also check if we run a 64 bit kernel.
To make the check perform well add the STCKF bit to the machine flags.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/include/asm/setup.h | 3 +++
 arch/s390/include/asm/timex.h | 2 +-
 arch/s390/kernel/early.c      | 2 ++
 3 files changed, 6 insertions(+), 1 deletion(-)

(limited to 'arch/s390')

diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index 5a099714df04..097183c70407 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -82,6 +82,7 @@ extern unsigned int user_mode;
 #define MACHINE_FLAG_LPAR	(1UL << 12)
 #define MACHINE_FLAG_SPP	(1UL << 13)
 #define MACHINE_FLAG_TOPOLOGY	(1UL << 14)
+#define MACHINE_FLAG_STCKF	(1UL << 15)
 
 #define MACHINE_IS_VM		(S390_lowcore.machine_flags & MACHINE_FLAG_VM)
 #define MACHINE_IS_KVM		(S390_lowcore.machine_flags & MACHINE_FLAG_KVM)
@@ -100,6 +101,7 @@ extern unsigned int user_mode;
 #define MACHINE_HAS_PFMF	(0)
 #define MACHINE_HAS_SPP		(0)
 #define MACHINE_HAS_TOPOLOGY	(0)
+#define MACHINE_HAS_STCKF	(0)
 #else /* __s390x__ */
 #define MACHINE_HAS_IEEE	(1)
 #define MACHINE_HAS_CSP		(1)
@@ -111,6 +113,7 @@ extern unsigned int user_mode;
 #define MACHINE_HAS_PFMF	(S390_lowcore.machine_flags & MACHINE_FLAG_PFMF)
 #define MACHINE_HAS_SPP		(S390_lowcore.machine_flags & MACHINE_FLAG_SPP)
 #define MACHINE_HAS_TOPOLOGY	(S390_lowcore.machine_flags & MACHINE_FLAG_TOPOLOGY)
+#define MACHINE_HAS_STCKF	(S390_lowcore.machine_flags & MACHINE_FLAG_STCKF)
 #endif /* __s390x__ */
 
 #define ZFCPDUMP_HSA_SIZE	(32UL<<20)
diff --git a/arch/s390/include/asm/timex.h b/arch/s390/include/asm/timex.h
index d610bef9c5e9..c447a27a7fdb 100644
--- a/arch/s390/include/asm/timex.h
+++ b/arch/s390/include/asm/timex.h
@@ -90,7 +90,7 @@ static inline unsigned long long get_clock_fast(void)
 {
 	unsigned long long clk;
 
-	if (test_facility(25))
+	if (MACHINE_HAS_STCKF)
 		asm volatile(".insn	s,0xb27c0000,%0" : "=Q" (clk) : : "cc");
 	else
 		clk = get_clock();
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 37394b3413e2..c9ffe0025197 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -390,6 +390,8 @@ static __init void detect_machine_facilities(void)
 		S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
 	if (test_facility(40))
 		S390_lowcore.machine_flags |= MACHINE_FLAG_SPP;
+	if (test_facility(25))
+		S390_lowcore.machine_flags |= MACHINE_FLAG_STCKF;
 #endif
 }
 
-- 
cgit v1.2.3


From 6ed54387dc470fc439cb154724a1ac81d251c126 Mon Sep 17 00:00:00 2001
From: Jan Glauber <jang@linux.vnet.ibm.com>
Date: Mon, 14 Nov 2011 11:19:07 +0100
Subject: [S390] crypto: avoid MSA3 and MSA4 instructions in ESA mode

MSA3 and MSA4 instructions are only available under CONFIG_64BIT.
Bail out before using any of these instructions if the kernel is
running in 31 bit mode.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/crypto/crypt_s390.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

(limited to 'arch/s390')

diff --git a/arch/s390/crypto/crypt_s390.h b/arch/s390/crypto/crypt_s390.h
index 49676771bd66..ffd1ac255f19 100644
--- a/arch/s390/crypto/crypt_s390.h
+++ b/arch/s390/crypto/crypt_s390.h
@@ -368,9 +368,12 @@ static inline int crypt_s390_func_available(int func,
 
 	if (facility_mask & CRYPT_S390_MSA && !test_facility(17))
 		return 0;
-	if (facility_mask & CRYPT_S390_MSA3 && !test_facility(76))
+
+	if (facility_mask & CRYPT_S390_MSA3 &&
+	    (!test_facility(2) || !test_facility(76)))
 		return 0;
-	if (facility_mask & CRYPT_S390_MSA4 && !test_facility(77))
+	if (facility_mask & CRYPT_S390_MSA4 &&
+	    (!test_facility(2) || !test_facility(77)))
 		return 0;
 
 	switch (func & CRYPT_S390_OP_MASK) {
-- 
cgit v1.2.3


From f6bf1a8acd2cb3a92a7b7c9ab03e56a32ac5ece5 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Mon, 14 Nov 2011 11:19:08 +0100
Subject: [S390] topology: fix topology on z10 machines

Make sure that all cpus in a book on a z10 appear as book siblings
and not as core siblings. This fixes some performance regressions that
appeared after the book scheduling domain got introduced.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/kernel/topology.c | 45 ++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 38 insertions(+), 7 deletions(-)

(limited to 'arch/s390')

diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c
index 77b8942b9a15..fdb5b8cb260f 100644
--- a/arch/s390/kernel/topology.c
+++ b/arch/s390/kernel/topology.c
@@ -68,8 +68,10 @@ static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu)
 	return mask;
 }
 
-static void add_cpus_to_mask(struct topology_cpu *tl_cpu,
-			     struct mask_info *book, struct mask_info *core)
+static struct mask_info *add_cpus_to_mask(struct topology_cpu *tl_cpu,
+					  struct mask_info *book,
+					  struct mask_info *core,
+					  int z10)
 {
 	unsigned int cpu;
 
@@ -88,10 +90,16 @@ static void add_cpus_to_mask(struct topology_cpu *tl_cpu,
 			cpu_book_id[lcpu] = book->id;
 #endif
 			cpumask_set_cpu(lcpu, &core->mask);
-			cpu_core_id[lcpu] = core->id;
+			if (z10) {
+				cpu_core_id[lcpu] = rcpu;
+				core = core->next;
+			} else {
+				cpu_core_id[lcpu] = core->id;
+			}
 			smp_cpu_polarization[lcpu] = tl_cpu->pp;
 		}
 	}
+	return core;
 }
 
 static void clear_masks(void)
@@ -123,18 +131,41 @@ static void tl_to_cores(struct sysinfo_15_1_x *info)
 {
 #ifdef CONFIG_SCHED_BOOK
 	struct mask_info *book = &book_info;
+	struct cpuid cpu_id;
 #else
 	struct mask_info *book = NULL;
 #endif
 	struct mask_info *core = &core_info;
 	union topology_entry *tle, *end;
+	int z10 = 0;
 
-
+#ifdef CONFIG_SCHED_BOOK
+	get_cpu_id(&cpu_id);
+	z10 = cpu_id.machine == 0x2097 || cpu_id.machine == 0x2098;
+#endif
 	spin_lock_irq(&topology_lock);
 	clear_masks();
 	tle = info->tle;
 	end = (union topology_entry *)((unsigned long)info + info->length);
 	while (tle < end) {
+#ifdef CONFIG_SCHED_BOOK
+		if (z10) {
+			switch (tle->nl) {
+			case 1:
+				book = book->next;
+				book->id = tle->container.id;
+				break;
+			case 0:
+				core = add_cpus_to_mask(&tle->cpu, book, core, z10);
+				break;
+			default:
+				clear_masks();
+				goto out;
+			}
+			tle = next_tle(tle);
+			continue;
+		}
+#endif
 		switch (tle->nl) {
 #ifdef CONFIG_SCHED_BOOK
 		case 2:
@@ -147,7 +178,7 @@ static void tl_to_cores(struct sysinfo_15_1_x *info)
 			core->id = tle->container.id;
 			break;
 		case 0:
-			add_cpus_to_mask(&tle->cpu, book, core);
+			add_cpus_to_mask(&tle->cpu, book, core, z10);
 			break;
 		default:
 			clear_masks();
@@ -328,8 +359,8 @@ void __init s390_init_cpu_topology(void)
 	for (i = 0; i < TOPOLOGY_NR_MAG; i++)
 		printk(" %d", info->mag[i]);
 	printk(" / %d\n", info->mnest);
-	alloc_masks(info, &core_info, 2);
+	alloc_masks(info, &core_info, 1);
 #ifdef CONFIG_SCHED_BOOK
-	alloc_masks(info, &book_info, 3);
+	alloc_masks(info, &book_info, 2);
 #endif
 }
-- 
cgit v1.2.3


From 9e6dabeffd1d0ec2aa19aa076c4886067238d442 Mon Sep 17 00:00:00 2001
From: Cornelia Huck <cornelia.huck@de.ibm.com>
Date: Thu, 17 Nov 2011 11:00:41 +0100
Subject: KVM: s390: Fix RUNNING flag misinterpretation

CPUSTAT_RUNNING was implemented signifying that a vcpu is not stopped.
This is not, however, what the architecture says: RUNNING should be
set when the host is acting on the behalf of the guest operating
system.

CPUSTAT_RUNNING has been changed to be set in kvm_arch_vcpu_load()
and to be unset in kvm_arch_vcpu_put().

For signifying stopped state of a vcpu, a host-controlled bit has
been used and is set/unset basically on the reverse as the old
CPUSTAT_RUNNING bit (including pushing it down into stop handling
proper in handle_stop()).

Cc: stable@kernel.org
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/s390/include/asm/kvm_host.h |  2 +-
 arch/s390/kvm/diag.c             |  2 +-
 arch/s390/kvm/intercept.c        |  3 ++-
 arch/s390/kvm/interrupt.c        |  1 +
 arch/s390/kvm/kvm-s390.c         | 10 +++++++---
 arch/s390/kvm/sigp.c             |  6 +++---
 6 files changed, 15 insertions(+), 9 deletions(-)

(limited to 'arch/s390')

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 24e18473d926..20f9068cd6b5 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -47,7 +47,7 @@ struct sca_block {
 #define KVM_HPAGE_MASK(x)	(~(KVM_HPAGE_SIZE(x) - 1))
 #define KVM_PAGES_PER_HPAGE(x)	(KVM_HPAGE_SIZE(x) / PAGE_SIZE)
 
-#define CPUSTAT_HOST       0x80000000
+#define CPUSTAT_STOPPED    0x80000000
 #define CPUSTAT_WAIT       0x10000000
 #define CPUSTAT_ECALL_PEND 0x08000000
 #define CPUSTAT_STOP_INT   0x04000000
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
index 87cedd61be04..8943e82cd4d9 100644
--- a/arch/s390/kvm/diag.c
+++ b/arch/s390/kvm/diag.c
@@ -70,7 +70,7 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
 		return -EOPNOTSUPP;
 	}
 
-	atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
+	atomic_set_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
 	vcpu->run->s390_reset_flags |= KVM_S390_RESET_SUBSYSTEM;
 	vcpu->run->s390_reset_flags |= KVM_S390_RESET_IPL;
 	vcpu->run->s390_reset_flags |= KVM_S390_RESET_CPU_INIT;
diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index c7c51898984e..02434543eabb 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -132,7 +132,6 @@ static int handle_stop(struct kvm_vcpu *vcpu)
 	int rc = 0;
 
 	vcpu->stat.exit_stop_request++;
-	atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
 	spin_lock_bh(&vcpu->arch.local_int.lock);
 	if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) {
 		vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP;
@@ -149,6 +148,8 @@ static int handle_stop(struct kvm_vcpu *vcpu)
 	}
 
 	if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) {
+		atomic_set_mask(CPUSTAT_STOPPED,
+				&vcpu->arch.sie_block->cpuflags);
 		vcpu->arch.local_int.action_bits &= ~ACTION_STOP_ON_STOP;
 		VCPU_EVENT(vcpu, 3, "%s", "cpu stopped");
 		rc = -EOPNOTSUPP;
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 87c16705b381..278ee009ce65 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -252,6 +252,7 @@ static void __do_deliver_interrupt(struct kvm_vcpu *vcpu,
 			offsetof(struct _lowcore, restart_psw), sizeof(psw_t));
 		if (rc == -EFAULT)
 			exception = 1;
+		atomic_clear_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
 		break;
 
 	case KVM_S390_PROGRAM_INT:
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 0bd3bea1e4cd..630ab65b488b 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -270,10 +270,12 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 	restore_fp_regs(&vcpu->arch.guest_fpregs);
 	restore_access_regs(vcpu->arch.guest_acrs);
 	gmap_enable(vcpu->arch.gmap);
+	atomic_set_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
 }
 
 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 {
+	atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
 	gmap_disable(vcpu->arch.gmap);
 	save_fp_regs(&vcpu->arch.guest_fpregs);
 	save_access_regs(vcpu->arch.guest_acrs);
@@ -301,7 +303,9 @@ static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu)
 
 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 {
-	atomic_set(&vcpu->arch.sie_block->cpuflags, CPUSTAT_ZARCH | CPUSTAT_SM);
+	atomic_set(&vcpu->arch.sie_block->cpuflags, CPUSTAT_ZARCH |
+						    CPUSTAT_SM |
+						    CPUSTAT_STOPPED);
 	vcpu->arch.sie_block->ecb   = 6;
 	vcpu->arch.sie_block->eca   = 0xC1002001U;
 	vcpu->arch.sie_block->fac   = (int) (long) facilities;
@@ -428,7 +432,7 @@ static int kvm_arch_vcpu_ioctl_set_initial_psw(struct kvm_vcpu *vcpu, psw_t psw)
 {
 	int rc = 0;
 
-	if (atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_RUNNING)
+	if (!(atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOPPED))
 		rc = -EBUSY;
 	else {
 		vcpu->run->psw_mask = psw.mask;
@@ -501,7 +505,7 @@ rerun_vcpu:
 	if (vcpu->sigset_active)
 		sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
 
-	atomic_set_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
+	atomic_clear_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
 
 	BUG_ON(vcpu->kvm->arch.float_int.local_int[vcpu->vcpu_id] == NULL);
 
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index f815118835f3..4a488a98d7f8 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -57,8 +57,8 @@ static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
 	spin_lock(&fi->lock);
 	if (fi->local_int[cpu_addr] == NULL)
 		rc = 3; /* not operational */
-	else if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
-		 & CPUSTAT_RUNNING) {
+	else if (!(atomic_read(fi->local_int[cpu_addr]->cpuflags)
+		  & CPUSTAT_STOPPED)) {
 		*reg &= 0xffffffff00000000UL;
 		rc = 1; /* status stored */
 	} else {
@@ -251,7 +251,7 @@ static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 
 	spin_lock_bh(&li->lock);
 	/* cpu must be in stopped state */
-	if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
+	if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 		rc = 1; /* incorrect state */
 		*reg &= SIGP_STAT_INCORRECT_STATE;
 		kfree(inti);
-- 
cgit v1.2.3


From bd59d3a4444e5f941c863db1a7715edf7289e29a Mon Sep 17 00:00:00 2001
From: Cornelia Huck <cornelia.huck@de.ibm.com>
Date: Thu, 17 Nov 2011 11:00:42 +0100
Subject: KVM: s390: handle SIGP sense running intercepts

SIGP sense running may cause an intercept on higher level
virtualization, so handle it by checking the CPUSTAT_RUNNING flag.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/s390/include/asm/kvm_host.h |  1 +
 arch/s390/kvm/kvm-s390.c         |  1 +
 arch/s390/kvm/sigp.c             | 39 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 41 insertions(+)

(limited to 'arch/s390')

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 20f9068cd6b5..b0c235cb6ad5 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -139,6 +139,7 @@ struct kvm_vcpu_stat {
 	u32 instruction_stfl;
 	u32 instruction_tprot;
 	u32 instruction_sigp_sense;
+	u32 instruction_sigp_sense_running;
 	u32 instruction_sigp_external_call;
 	u32 instruction_sigp_emergency;
 	u32 instruction_sigp_stop;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 630ab65b488b..0891926ea953 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -65,6 +65,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
 	{ "instruction_stfl", VCPU_STAT(instruction_stfl) },
 	{ "instruction_tprot", VCPU_STAT(instruction_tprot) },
 	{ "instruction_sigp_sense", VCPU_STAT(instruction_sigp_sense) },
+	{ "instruction_sigp_sense_running", VCPU_STAT(instruction_sigp_sense_running) },
 	{ "instruction_sigp_external_call", VCPU_STAT(instruction_sigp_external_call) },
 	{ "instruction_sigp_emergency", VCPU_STAT(instruction_sigp_emergency) },
 	{ "instruction_sigp_stop", VCPU_STAT(instruction_sigp_stop) },
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index 4a488a98d7f8..0a7941d74bc6 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -31,9 +31,11 @@
 #define SIGP_SET_PREFIX        0x0d
 #define SIGP_STORE_STATUS_ADDR 0x0e
 #define SIGP_SET_ARCH          0x12
+#define SIGP_SENSE_RUNNING     0x15
 
 /* cpu status bits */
 #define SIGP_STAT_EQUIPMENT_CHECK   0x80000000UL
+#define SIGP_STAT_NOT_RUNNING	    0x00000400UL
 #define SIGP_STAT_INCORRECT_STATE   0x00000200UL
 #define SIGP_STAT_INVALID_PARAMETER 0x00000100UL
 #define SIGP_STAT_EXT_CALL_PENDING  0x00000080UL
@@ -275,6 +277,38 @@ out_fi:
 	return rc;
 }
 
+static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
+				unsigned long *reg)
+{
+	int rc;
+	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
+
+	if (cpu_addr >= KVM_MAX_VCPUS)
+		return 3; /* not operational */
+
+	spin_lock(&fi->lock);
+	if (fi->local_int[cpu_addr] == NULL)
+		rc = 3; /* not operational */
+	else {
+		if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
+		    & CPUSTAT_RUNNING) {
+			/* running */
+			rc = 1;
+		} else {
+			/* not running */
+			*reg &= 0xffffffff00000000UL;
+			*reg |= SIGP_STAT_NOT_RUNNING;
+			rc = 0;
+		}
+	}
+	spin_unlock(&fi->lock);
+
+	VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x", cpu_addr,
+		   rc);
+
+	return rc;
+}
+
 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 {
 	int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
@@ -331,6 +365,11 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 		rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
 				       &vcpu->arch.guest_gprs[r1]);
 		break;
+	case SIGP_SENSE_RUNNING:
+		vcpu->stat.instruction_sigp_sense_running++;
+		rc = __sigp_sense_running(vcpu, cpu_addr,
+					  &vcpu->arch.guest_gprs[r1]);
+		break;
 	case SIGP_RESTART:
 		vcpu->stat.instruction_sigp_restart++;
 		/* user space must know about restart */
-- 
cgit v1.2.3


From 1eddb85f889a5a9fe59ec184e06844716a00aded Mon Sep 17 00:00:00 2001
From: Christian Borntraeger <borntraeger@de.ibm.com>
Date: Thu, 17 Nov 2011 11:00:43 +0100
Subject: KVM: s390: Fix tprot locking

There is a potential host deadlock in the tprot intercept handling.
We must not hold the mmap semaphore while resolving the guest
address. If userspace is remapping, then the memory detection in
the guest is broken anyway so we can safely separate the
address translation from walking the vmas.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/s390/kvm/priv.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

(limited to 'arch/s390')

diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 391626361084..d02638959922 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -336,6 +336,7 @@ static int handle_tprot(struct kvm_vcpu *vcpu)
 	u64 address1 = disp1 + base1 ? vcpu->arch.guest_gprs[base1] : 0;
 	u64 address2 = disp2 + base2 ? vcpu->arch.guest_gprs[base2] : 0;
 	struct vm_area_struct *vma;
+	unsigned long user_address;
 
 	vcpu->stat.instruction_tprot++;
 
@@ -349,9 +350,14 @@ static int handle_tprot(struct kvm_vcpu *vcpu)
 		return -EOPNOTSUPP;
 
 
+	/* we must resolve the address without holding the mmap semaphore.
+	 * This is ok since the userspace hypervisor is not supposed to change
+	 * the mapping while the guest queries the memory. Otherwise the guest
+	 * might crash or get wrong info anyway. */
+	user_address = (unsigned long) __guestaddr_to_user(vcpu, address1);
+
 	down_read(&current->mm->mmap_sem);
-	vma = find_vma(current->mm,
-			(unsigned long) __guestaddr_to_user(vcpu, address1));
+	vma = find_vma(current->mm, user_address);
 	if (!vma) {
 		up_read(&current->mm->mmap_sem);
 		return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
-- 
cgit v1.2.3


From 52e16b185fdd0aeb0522c203e944873e38ac1575 Mon Sep 17 00:00:00 2001
From: Christian Borntraeger <borntraeger@de.ibm.com>
Date: Thu, 17 Nov 2011 11:00:44 +0100
Subject: KVM: s390: announce SYNC_MMU

KVM on s390 always had a sync mmu. Any mapping change in userspace
mapping was always reflected immediately in the guest mapping.
- In older code the guest mapping was just an offset
- In newer code the last level page table is shared

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/s390/kvm/kvm-s390.c | 1 +
 1 file changed, 1 insertion(+)

(limited to 'arch/s390')

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 0891926ea953..d1c445732451 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -128,6 +128,7 @@ int kvm_dev_ioctl_check_extension(long ext)
 	switch (ext) {
 	case KVM_CAP_S390_PSW:
 	case KVM_CAP_S390_GMAP:
+	case KVM_CAP_SYNC_MMU:
 		r = 1;
 		break;
 	default:
-- 
cgit v1.2.3


From 5f894cbb6890d317699aa622b4dc9d73d009cd22 Mon Sep 17 00:00:00 2001
From: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Date: Thu, 1 Dec 2011 13:32:14 +0100
Subject: [S390] kdump: Replace is_kdump_kernel() with OLDMEM_BASE check

In order to have the same behavior for kdump based stand-alone dump
as for the kexec method, the is_kdump_kernel() check (only true for
the kexec method) has to be replaced by the OLDMEM_BASE check (true
for both methods).

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/kernel/setup.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'arch/s390')

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index e58a462949b1..e54c4ff8abaa 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -579,7 +579,7 @@ static unsigned long __init find_crash_base(unsigned long crash_size,
 		*msg = "first memory chunk must be at least crashkernel size";
 		return 0;
 	}
-	if (is_kdump_kernel() && (crash_size == OLDMEM_SIZE))
+	if (OLDMEM_BASE && crash_size == OLDMEM_SIZE)
 		return OLDMEM_BASE;
 
 	for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
-- 
cgit v1.2.3


From d9ae6772d3a3d7325d535577d9fd09c0de8a9da3 Mon Sep 17 00:00:00 2001
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Date: Thu, 1 Dec 2011 13:32:15 +0100
Subject: [S390] ptrace inferior call interactions with TIF_SYSCALL

The TIF_SYSCALL bit needs to be cleared if the debugger changes the state
of the ptraced process in regard to the presence of a system call.
Otherwise the system call will be restarted although the debugger set up
an inferior call.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/kernel/signal.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

(limited to 'arch/s390')

diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 05a85bc14c98..7f6f9f354545 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -460,9 +460,9 @@ void do_signal(struct pt_regs *regs)
 						     regs->svc_code >> 16);
 				break;
 			}
-			/* No longer in a system call */
-			clear_thread_flag(TIF_SYSCALL);
 		}
+		/* No longer in a system call */
+		clear_thread_flag(TIF_SYSCALL);
 
 		if ((is_compat_task() ?
 		     handle_signal32(signr, &ka, &info, oldset, regs) :
@@ -486,6 +486,7 @@ void do_signal(struct pt_regs *regs)
 	}
 
 	/* No handlers present - check for system call restart */
+	clear_thread_flag(TIF_SYSCALL);
 	if (current_thread_info()->system_call) {
 		regs->svc_code = current_thread_info()->system_call;
 		switch (regs->gprs[2]) {
@@ -500,9 +501,6 @@ void do_signal(struct pt_regs *regs)
 			regs->gprs[2] = regs->orig_gpr2;
 			set_thread_flag(TIF_SYSCALL);
 			break;
-		default:
-			clear_thread_flag(TIF_SYSCALL);
-			break;
 		}
 	}
 
-- 
cgit v1.2.3


From 7c81878b34dd1b75dec5c8b68951d1439854d358 Mon Sep 17 00:00:00 2001
From: Carsten Otte <cotte@de.ibm.com>
Date: Thu, 1 Dec 2011 13:32:16 +0100
Subject: [S390] fix page change underindication in pgste_update_all

This patch makes sure we don't underindicate _PAGE_CHANGED in case
we have a race between an operation that changes the page and this
code path that hits us between page_get_storage_key and
page_set_storage_key. Note that we still have a potential
underindication on _PAGE_REFERENCED in the unlikely event that
the page was changed but not referenced _and_ someone references
the page in the race window. That's not considered to be a problem.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/include/asm/pgtable.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

(limited to 'arch/s390')

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 524d23b8610c..4f289ff0b7fe 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -599,10 +599,10 @@ static inline pgste_t pgste_update_all(pte_t *ptep, pgste_t pgste)
 	skey = page_get_storage_key(address);
 	bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
 	/* Clear page changed & referenced bit in the storage key */
-	if (bits) {
-		skey ^= bits;
-		page_set_storage_key(address, skey, 1);
-	}
+	if (bits & _PAGE_CHANGED)
+		page_set_storage_key(address, skey ^ bits, 1);
+	else if (bits)
+		page_reset_referenced(address);
 	/* Transfer page changed & referenced bit to guest bits in pgste */
 	pgste_val(pgste) |= bits << 48;		/* RCP_GR_BIT & RCP_GC_BIT */
 	/* Get host changed & referenced bits from pgste */
-- 
cgit v1.2.3


From b934069c991355d27a053a932591c77960f4e414 Mon Sep 17 00:00:00 2001
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Date: Thu, 1 Dec 2011 13:32:17 +0100
Subject: [S390] add missing .set function for NT_S390_LAST_BREAK regset

The last breaking event address is a read-only value, the regset misses the
.set function. If a PTRACE_SETREGSET is done for NT_S390_LAST_BREAK we
get an oops due to a branch to zero:

Kernel BUG at 0000000000000002 verbose debug info unavailable
illegal operation: 0001 #1 SMP
...
Call Trace:
(<0000000000158294> ptrace_regset+0x184/0x188)
 <00000000001595b6> ptrace_request+0x37a/0x4fc
 <0000000000109a78> arch_ptrace+0x108/0x1fc
 <00000000001590d6> SyS_ptrace+0xaa/0x12c
 <00000000005c7a42> sysc_noemu+0x16/0x1c
 <000003fffd5ec10c> 0x3fffd5ec10c
Last Breaking-Event-Address:
 <0000000000158242> ptrace_regset+0x132/0x188

Add a nop .set function to prevent the branch to zero.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: stable@kernel.org
---
 arch/s390/kernel/ptrace.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

(limited to 'arch/s390')

diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index 450931a45b68..f05649fd0547 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -905,6 +905,14 @@ static int s390_last_break_get(struct task_struct *target,
 	return 0;
 }
 
+static int s390_last_break_set(struct task_struct *target,
+			       const struct user_regset *regset,
+			       unsigned int pos, unsigned int count,
+			       const void *kbuf, const void __user *ubuf)
+{
+	return 0;
+}
+
 #endif
 
 static int s390_system_call_get(struct task_struct *target,
@@ -951,6 +959,7 @@ static const struct user_regset s390_regsets[] = {
 		.size = sizeof(long),
 		.align = sizeof(long),
 		.get = s390_last_break_get,
+		.set = s390_last_break_set,
 	},
 #endif
 	[REGSET_SYSTEM_CALL] = {
@@ -1116,6 +1125,14 @@ static int s390_compat_last_break_get(struct task_struct *target,
 	return 0;
 }
 
+static int s390_compat_last_break_set(struct task_struct *target,
+				      const struct user_regset *regset,
+				      unsigned int pos, unsigned int count,
+				      const void *kbuf, const void __user *ubuf)
+{
+	return 0;
+}
+
 static const struct user_regset s390_compat_regsets[] = {
 	[REGSET_GENERAL] = {
 		.core_note_type = NT_PRSTATUS,
@@ -1139,6 +1156,7 @@ static const struct user_regset s390_compat_regsets[] = {
 		.size = sizeof(long),
 		.align = sizeof(long),
 		.get = s390_compat_last_break_get,
+		.set = s390_compat_last_break_set,
 	},
 	[REGSET_SYSTEM_CALL] = {
 		.core_note_type = NT_S390_SYSTEM_CALL,
-- 
cgit v1.2.3


From cfc9066bcd3ab498268e1d075f1556bb5244c0aa Mon Sep 17 00:00:00 2001
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Date: Thu, 1 Dec 2011 13:32:18 +0100
Subject: [S390] remove reset of system call restart on psw changes

git commit 20b40a794baf3b4b "signal race with restarting system calls"
added code to the poke_user/poke_user_compat to reset the system call
restart information in the thread-info if the PSW address is changed.
The purpose of that change has been to workaround old gdbs that do
not know about the REGSET_SYSTEM_CALL. It turned out that this is not
a good idea, it makes the behaviour of the debuggee dependent on the
order of specific ptrace call, e.g. the REGSET_SYSTEM_CALL register
set needs to be written last. And the workaround does not really fix
old gdbs, inferior calls on interrupted restarting system calls do not
work either way.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/kernel/ptrace.c | 12 ------------
 1 file changed, 12 deletions(-)

(limited to 'arch/s390')

diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index f05649fd0547..573bc29551ef 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -296,13 +296,6 @@ static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 		     ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))))
 			/* Invalid psw mask. */
 			return -EINVAL;
-		if (addr == (addr_t) &dummy->regs.psw.addr)
-			/*
-			 * The debugger changed the instruction address,
-			 * reset system call restart, see signal.c:do_signal
-			 */
-			task_thread_info(child)->system_call = 0;
-
 		*(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
 
 	} else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
@@ -614,11 +607,6 @@ static int __poke_user_compat(struct task_struct *child,
 			/* Transfer 31 bit amode bit to psw mask. */
 			regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
 				(__u64)(tmp & PSW32_ADDR_AMODE);
-			/*
-			 * The debugger changed the instruction address,
-			 * reset system call restart, see signal.c:do_signal
-			 */
-			task_thread_info(child)->system_call = 0;
 		} else {
 			/* gpr 0-15 */
 			*(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
-- 
cgit v1.2.3