From e8129c642155616d9e2160a75f103e127c8c3708 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Thu, 25 Nov 2010 09:52:45 +0100 Subject: [S390] nmi: fix clock comparator revalidation On each machine check all registers are revalidated. The save area for the clock comparator however only contains the upper most seven bytes of the former contents, if valid. Therefore the machine check handler uses a store clock instruction to get the current time and writes that to the clock comparator register which in turn will generate an immediate timer interrupt. However within the lowcore the expected time of the next timer interrupt is stored. If the interrupt happens before that time the handler won't be called. In turn the clock comparator won't be reprogrammed and therefore the interrupt condition stays pending which causes an interrupt loop until the expected time is reached. On NOHZ machines this can result in unresponsive machines since the time of the next expected interrupted can be a couple of days in the future. To fix this just revalidate the clock comparator register with the expected value. In addition the special handling for udelay must be changed as well. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/lib/delay.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) (limited to 'arch/s390/lib') diff --git a/arch/s390/lib/delay.c b/arch/s390/lib/delay.c index 752b362bf651..7c37ec359ec2 100644 --- a/arch/s390/lib/delay.c +++ b/arch/s390/lib/delay.c @@ -29,17 +29,21 @@ static void __udelay_disabled(unsigned long long usecs) { unsigned long mask, cr0, cr0_saved; u64 clock_saved; + u64 end; + mask = psw_kernel_bits | PSW_MASK_WAIT | PSW_MASK_EXT; + end = get_clock() + (usecs << 12); clock_saved = local_tick_disable(); - set_clock_comparator(get_clock() + (usecs << 12)); __ctl_store(cr0_saved, 0, 0); cr0 = (cr0_saved & 0xffff00e0) | 0x00000800; __ctl_load(cr0 , 0, 0); - mask = psw_kernel_bits | PSW_MASK_WAIT | PSW_MASK_EXT; lockdep_off(); - trace_hardirqs_on(); - __load_psw_mask(mask); - local_irq_disable(); + do { + set_clock_comparator(end); + trace_hardirqs_on(); + __load_psw_mask(mask); + local_irq_disable(); + } while (get_clock() < end); lockdep_on(); __ctl_load(cr0_saved, 0, 0); local_tick_enable(clock_saved); -- cgit v1.2.2 From 545b288dcbdea58a2ce2afba5f6a8302d31ac459 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 5 Jan 2011 12:47:27 +0100 Subject: [S390] time: let local_tick_enable/disable() reprogram the clock comparator Let local_tick_enable/disable() reprogram the clock comparator so the function names make semantically more sense. Also that way the functions are more symmetric since normally each local_tick_enable() call usually would have a subsequent call to set_clock_comparator() anyway. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/lib/delay.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/s390/lib') diff --git a/arch/s390/lib/delay.c b/arch/s390/lib/delay.c index 7c37ec359ec2..0f53110e1d09 100644 --- a/arch/s390/lib/delay.c +++ b/arch/s390/lib/delay.c @@ -47,7 +47,6 @@ static void __udelay_disabled(unsigned long long usecs) lockdep_on(); __ctl_load(cr0_saved, 0, 0); local_tick_enable(clock_saved); - set_clock_comparator(S390_lowcore.clock_comparator); } static void __udelay_enabled(unsigned long long usecs) @@ -70,7 +69,6 @@ static void __udelay_enabled(unsigned long long usecs) if (clock_saved) local_tick_enable(clock_saved); } while (get_clock() < end); - set_clock_comparator(S390_lowcore.clock_comparator); } /* -- cgit v1.2.2 From e4d82692f4513ccf78de548b8ecea58adf03fa9a Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Mon, 31 Jan 2011 11:30:05 +0100 Subject: [S390] missing sacf in uaccess The uaccess functions copy_in_user_std and clear_user_std fail to switch back from secondary space mode to primary space mode with sacf in case of an unresolvable page fault. We need to make sure that the switch back to primary mode is done in all cases, otherwise the code following the uaccess inline assembly will crash. Reported-by: Alexander Graf Signed-off-by: Martin Schwidefsky --- arch/s390/lib/uaccess_std.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'arch/s390/lib') diff --git a/arch/s390/lib/uaccess_std.c b/arch/s390/lib/uaccess_std.c index 07deaeee14c8..a6c4f7ed24a4 100644 --- a/arch/s390/lib/uaccess_std.c +++ b/arch/s390/lib/uaccess_std.c @@ -125,9 +125,9 @@ static size_t copy_in_user_std(size_t size, void __user *to, unsigned long tmp1; asm volatile( + " sacf 256\n" " "AHI" %0,-1\n" " jo 5f\n" - " sacf 256\n" " bras %3,3f\n" "0:"AHI" %0,257\n" "1: mvc 0(1,%1),0(%2)\n" @@ -142,9 +142,8 @@ static size_t copy_in_user_std(size_t size, void __user *to, "3:"AHI" %0,-256\n" " jnm 2b\n" "4: ex %0,1b-0b(%3)\n" - " sacf 0\n" "5: "SLR" %0,%0\n" - "6:\n" + "6: sacf 0\n" EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b) : "+a" (size), "+a" (to), "+a" (from), "=a" (tmp1) : : "cc", "memory"); @@ -156,9 +155,9 @@ static size_t clear_user_std(size_t size, void __user *to) unsigned long tmp1, tmp2; asm volatile( + " sacf 256\n" " "AHI" %0,-1\n" " jo 5f\n" - " sacf 256\n" " bras %3,3f\n" " xc 0(1,%1),0(%1)\n" "0:"AHI" %0,257\n" @@ -178,9 +177,8 @@ static size_t clear_user_std(size_t size, void __user *to) "3:"AHI" %0,-256\n" " jnm 2b\n" "4: ex %0,0(%3)\n" - " sacf 0\n" "5: "SLR" %0,%0\n" - "6:\n" + "6: sacf 0\n" EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b) : "+a" (size), "+a" (to), "=a" (tmp1), "=a" (tmp2) : : "cc", "memory"); -- cgit v1.2.2 From 37a9d912b24f96a0591773e6e6c3642991ae5a70 Mon Sep 17 00:00:00 2001 From: Michel Lespinasse Date: Thu, 10 Mar 2011 18:48:51 -0800 Subject: futex: Sanitize cmpxchg_futex_value_locked API The cmpxchg_futex_value_locked API was funny in that it returned either the original, user-exposed futex value OR an error code such as -EFAULT. This was confusing at best, and could be a source of livelocks in places that retry the cmpxchg_futex_value_locked after trying to fix the issue by running fault_in_user_writeable(). This change makes the cmpxchg_futex_value_locked API more similar to the get_futex_value_locked one, returning an error code and updating the original value through a reference argument. Signed-off-by: Michel Lespinasse Acked-by: Chris Metcalf [tile] Acked-by: Tony Luck [ia64] Acked-by: Thomas Gleixner Tested-by: Michal Simek [microblaze] Acked-by: David Howells [frv] Cc: Darren Hart Cc: Peter Zijlstra Cc: Matt Turner Cc: Russell King Cc: Ralf Baechle Cc: "James E.J. Bottomley" Cc: Benjamin Herrenschmidt Cc: Martin Schwidefsky Cc: Paul Mundt Cc: "David S. Miller" Cc: Linus Torvalds LKML-Reference: <20110311024851.GC26122@google.com> Signed-off-by: Thomas Gleixner --- arch/s390/lib/uaccess.h | 4 ++-- arch/s390/lib/uaccess_pt.c | 13 ++++++++----- arch/s390/lib/uaccess_std.c | 6 ++++-- 3 files changed, 14 insertions(+), 9 deletions(-) (limited to 'arch/s390/lib') diff --git a/arch/s390/lib/uaccess.h b/arch/s390/lib/uaccess.h index 126011df14f1..89a80674e44b 100644 --- a/arch/s390/lib/uaccess.h +++ b/arch/s390/lib/uaccess.h @@ -12,12 +12,12 @@ extern size_t copy_from_user_std(size_t, const void __user *, void *); extern size_t copy_to_user_std(size_t, void __user *, const void *); extern size_t strnlen_user_std(size_t, const char __user *); extern size_t strncpy_from_user_std(size_t, const char __user *, char *); -extern int futex_atomic_cmpxchg_std(int __user *, int, int); +extern int futex_atomic_cmpxchg_std(int *, int __user *, int, int); extern int futex_atomic_op_std(int, int __user *, int, int *); extern size_t copy_from_user_pt(size_t, const void __user *, void *); extern size_t copy_to_user_pt(size_t, void __user *, const void *); extern int futex_atomic_op_pt(int, int __user *, int, int *); -extern int futex_atomic_cmpxchg_pt(int __user *, int, int); +extern int futex_atomic_cmpxchg_pt(int *, int __user *, int, int); #endif /* __ARCH_S390_LIB_UACCESS_H */ diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c index 404f2de296dc..b3cebcd52f5c 100644 --- a/arch/s390/lib/uaccess_pt.c +++ b/arch/s390/lib/uaccess_pt.c @@ -354,26 +354,29 @@ int futex_atomic_op_pt(int op, int __user *uaddr, int oparg, int *old) return ret; } -static int __futex_atomic_cmpxchg_pt(int __user *uaddr, int oldval, int newval) +static int __futex_atomic_cmpxchg_pt(int *uval, int __user *uaddr, + int oldval, int newval) { int ret; asm volatile("0: cs %1,%4,0(%5)\n" - "1: lr %0,%1\n" + "1: la %0,0\n" "2:\n" EX_TABLE(0b,2b) EX_TABLE(1b,2b) : "=d" (ret), "+d" (oldval), "=m" (*uaddr) : "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr) : "cc", "memory" ); + *uval = oldval; return ret; } -int futex_atomic_cmpxchg_pt(int __user *uaddr, int oldval, int newval) +int futex_atomic_cmpxchg_pt(int *uval, int __user *uaddr, + int oldval, int newval) { int ret; if (segment_eq(get_fs(), KERNEL_DS)) - return __futex_atomic_cmpxchg_pt(uaddr, oldval, newval); + return __futex_atomic_cmpxchg_pt(uval, uaddr, oldval, newval); spin_lock(¤t->mm->page_table_lock); uaddr = (int __user *) __dat_user_addr((unsigned long) uaddr); if (!uaddr) { @@ -382,7 +385,7 @@ int futex_atomic_cmpxchg_pt(int __user *uaddr, int oldval, int newval) } get_page(virt_to_page(uaddr)); spin_unlock(¤t->mm->page_table_lock); - ret = __futex_atomic_cmpxchg_pt(uaddr, oldval, newval); + ret = __futex_atomic_cmpxchg_pt(uval, uaddr, oldval, newval); put_page(virt_to_page(uaddr)); return ret; } diff --git a/arch/s390/lib/uaccess_std.c b/arch/s390/lib/uaccess_std.c index a6c4f7ed24a4..1d6643c0b95f 100644 --- a/arch/s390/lib/uaccess_std.c +++ b/arch/s390/lib/uaccess_std.c @@ -287,19 +287,21 @@ int futex_atomic_op_std(int op, int __user *uaddr, int oparg, int *old) return ret; } -int futex_atomic_cmpxchg_std(int __user *uaddr, int oldval, int newval) +int futex_atomic_cmpxchg_std(int *uval, int __user *uaddr, + int oldval, int newval) { int ret; asm volatile( " sacf 256\n" "0: cs %1,%4,0(%5)\n" - "1: lr %0,%1\n" + "1: la %0,0\n" "2: sacf 0\n" EX_TABLE(0b,2b) EX_TABLE(1b,2b) : "=d" (ret), "+d" (oldval), "=m" (*uaddr) : "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr) : "cc", "memory" ); + *uval = oldval; return ret; } -- cgit v1.2.2 From 8d7718aa082aaf30a0b4989e1f04858952f941bc Mon Sep 17 00:00:00 2001 From: Michel Lespinasse Date: Thu, 10 Mar 2011 18:50:58 -0800 Subject: futex: Sanitize futex ops argument types Change futex_atomic_op_inuser and futex_atomic_cmpxchg_inatomic prototypes to use u32 types for the futex as this is the data type the futex core code uses all over the place. Signed-off-by: Michel Lespinasse Cc: Darren Hart Cc: Peter Zijlstra Cc: Matt Turner Cc: Russell King Cc: David Howells Cc: Tony Luck Cc: Michal Simek Cc: Ralf Baechle Cc: "James E.J. Bottomley" Cc: Benjamin Herrenschmidt Cc: Martin Schwidefsky Cc: Paul Mundt Cc: "David S. Miller" Cc: Chris Metcalf Cc: Linus Torvalds LKML-Reference: <20110311025058.GD26122@google.com> Signed-off-by: Thomas Gleixner --- arch/s390/lib/uaccess.h | 8 ++++---- arch/s390/lib/uaccess_pt.c | 12 ++++++------ arch/s390/lib/uaccess_std.c | 6 +++--- 3 files changed, 13 insertions(+), 13 deletions(-) (limited to 'arch/s390/lib') diff --git a/arch/s390/lib/uaccess.h b/arch/s390/lib/uaccess.h index 89a80674e44b..1d2536cb630b 100644 --- a/arch/s390/lib/uaccess.h +++ b/arch/s390/lib/uaccess.h @@ -12,12 +12,12 @@ extern size_t copy_from_user_std(size_t, const void __user *, void *); extern size_t copy_to_user_std(size_t, void __user *, const void *); extern size_t strnlen_user_std(size_t, const char __user *); extern size_t strncpy_from_user_std(size_t, const char __user *, char *); -extern int futex_atomic_cmpxchg_std(int *, int __user *, int, int); -extern int futex_atomic_op_std(int, int __user *, int, int *); +extern int futex_atomic_cmpxchg_std(u32 *, u32 __user *, u32, u32); +extern int futex_atomic_op_std(int, u32 __user *, int, int *); extern size_t copy_from_user_pt(size_t, const void __user *, void *); extern size_t copy_to_user_pt(size_t, void __user *, const void *); -extern int futex_atomic_op_pt(int, int __user *, int, int *); -extern int futex_atomic_cmpxchg_pt(int *, int __user *, int, int); +extern int futex_atomic_op_pt(int, u32 __user *, int, int *); +extern int futex_atomic_cmpxchg_pt(u32 *, u32 __user *, u32, u32); #endif /* __ARCH_S390_LIB_UACCESS_H */ diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c index b3cebcd52f5c..74833831417f 100644 --- a/arch/s390/lib/uaccess_pt.c +++ b/arch/s390/lib/uaccess_pt.c @@ -302,7 +302,7 @@ fault: : "0" (-EFAULT), "d" (oparg), "a" (uaddr), \ "m" (*uaddr) : "cc" ); -static int __futex_atomic_op_pt(int op, int __user *uaddr, int oparg, int *old) +static int __futex_atomic_op_pt(int op, u32 __user *uaddr, int oparg, int *old) { int oldval = 0, newval, ret; @@ -335,7 +335,7 @@ static int __futex_atomic_op_pt(int op, int __user *uaddr, int oparg, int *old) return ret; } -int futex_atomic_op_pt(int op, int __user *uaddr, int oparg, int *old) +int futex_atomic_op_pt(int op, u32 __user *uaddr, int oparg, int *old) { int ret; @@ -354,8 +354,8 @@ int futex_atomic_op_pt(int op, int __user *uaddr, int oparg, int *old) return ret; } -static int __futex_atomic_cmpxchg_pt(int *uval, int __user *uaddr, - int oldval, int newval) +static int __futex_atomic_cmpxchg_pt(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) { int ret; @@ -370,8 +370,8 @@ static int __futex_atomic_cmpxchg_pt(int *uval, int __user *uaddr, return ret; } -int futex_atomic_cmpxchg_pt(int *uval, int __user *uaddr, - int oldval, int newval) +int futex_atomic_cmpxchg_pt(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) { int ret; diff --git a/arch/s390/lib/uaccess_std.c b/arch/s390/lib/uaccess_std.c index 1d6643c0b95f..bb1a7eed42ce 100644 --- a/arch/s390/lib/uaccess_std.c +++ b/arch/s390/lib/uaccess_std.c @@ -255,7 +255,7 @@ size_t strncpy_from_user_std(size_t size, const char __user *src, char *dst) : "0" (-EFAULT), "d" (oparg), "a" (uaddr), \ "m" (*uaddr) : "cc"); -int futex_atomic_op_std(int op, int __user *uaddr, int oparg, int *old) +int futex_atomic_op_std(int op, u32 __user *uaddr, int oparg, int *old) { int oldval = 0, newval, ret; @@ -287,8 +287,8 @@ int futex_atomic_op_std(int op, int __user *uaddr, int oparg, int *old) return ret; } -int futex_atomic_cmpxchg_std(int *uval, int __user *uaddr, - int oldval, int newval) +int futex_atomic_cmpxchg_std(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) { int ret; -- cgit v1.2.2 From b396637841fff79e9520514e8dcbe769c20a2ea0 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Thu, 26 May 2011 09:48:28 +0200 Subject: [S390] delay: implement ndelay Implement ndelay() on s390 as well. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/lib/delay.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'arch/s390/lib') diff --git a/arch/s390/lib/delay.c b/arch/s390/lib/delay.c index 0f53110e1d09..a65229d91c92 100644 --- a/arch/s390/lib/delay.c +++ b/arch/s390/lib/delay.c @@ -12,6 +12,7 @@ #include #include #include +#include void __delay(unsigned long loops) { @@ -116,3 +117,17 @@ void udelay_simple(unsigned long long usecs) while (get_clock() < end) cpu_relax(); } + +void __ndelay(unsigned long long nsecs) +{ + u64 end; + + nsecs <<= 9; + do_div(nsecs, 125); + end = get_clock() + nsecs; + if (nsecs & ~0xfffUL) + __udelay(nsecs >> 12); + while (get_clock() < end) + barrier(); +} +EXPORT_SYMBOL(__ndelay); -- cgit v1.2.2