Merge branch 'parisc-4.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux

96f893ab · Linus Torvalds <[email protected]> · 2017-10-19 16:18:58 -04:00

Pull parisc fixes from Helge Deller:
 "Three small important fixes for the parisc architecture:

   - Export __cmpxchg_u64() symbol on 32bit kernel too. This unbreaks
     building the kernel with ixgbe kernel module. From Guenter Roeck.

   - Fix 64-bit atomic cmpxchg kernel helper function for 32-bit kernel
     in LWS code for userspace. This unbreaks e.g. the 64-bit variant of
     the glibc function __sync_fetch_and_add() with a 32-bit parisc
     kernel. From John David Anglin, tagged for backport to v3.13+.

   - Detect nonsynchronous CPU-internal cr16 cycle counters more
     reliable. This avoids stalled CPU warnings by the kernel soft
     lockup detector. From me, tagged for backport to v4.13+"

* 'parisc-4.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Fix detection of nonsynchronous cr16 cycle counters
  parisc: Export __cmpxchg_u64 unconditionally
  parisc: Fix double-word compare and exchange in LWS code on 32-bit kernels

Commit: 96f893abc87bd29339c973edf6068a064cb8a756
Parents: 962556b5 · 8642b31b

Merge commit. Changes below are compared with the first parent: 962556b5.

Changes

3 files changed · +8 −5

File	Status	Add	Del	Content
arch/parisc/kernel/parisc_ksyms.c	modified	+1	−1	View file
arch/parisc/kernel/syscall.S	modified	+3	−3	View file
arch/parisc/kernel/time.c	modified	+4	−1	View file

arch/parisc/kernel/parisc_ksyms.c

View file

diff --git a/arch/parisc/kernel/parisc_ksyms.c b/arch/parisc/kernel/parisc_ksyms.c
index c6d6272..7baa226 100644
--- a/arch/parisc/kernel/parisc_ksyms.c
+++ b/arch/parisc/kernel/parisc_ksyms.c
@@ -35,12 +35,12 @@ EXPORT_SYMBOL(memset);
 EXPORT_SYMBOL(__xchg8);
 EXPORT_SYMBOL(__xchg32);
 EXPORT_SYMBOL(__cmpxchg_u32);
+EXPORT_SYMBOL(__cmpxchg_u64);
 #ifdef CONFIG_SMP
 EXPORT_SYMBOL(__atomic_hash);
 #endif
 #ifdef CONFIG_64BIT
 EXPORT_SYMBOL(__xchg64);
-EXPORT_SYMBOL(__cmpxchg_u64);
 #endif
 
 #include <linux/uaccess.h>

arch/parisc/kernel/syscall.S

View file

diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S
index 23de307..41e60a9 100644
--- a/arch/parisc/kernel/syscall.S
+++ b/arch/parisc/kernel/syscall.S
@@ -742,7 +742,7 @@ lws_compare_and_swap_2:
 10:	ldd	0(%r25), %r25
 11:	ldd	0(%r24), %r24
 #else
-	/* Load new value into r22/r23 - high/low */
+	/* Load old value into r22/r23 - high/low */
 10:	ldw	0(%r25), %r22
 11:	ldw	4(%r25), %r23
 	/* Load new value into fr4 for atomic store later */
@@ -834,11 +834,11 @@ cas2_action:
 	copy	%r0, %r28
 #else
 	/* Compare first word */
-19:	ldw,ma	0(%r26), %r29
+19:	ldw	0(%r26), %r29
 	sub,=	%r29, %r22, %r0
 	b,n	cas2_end
 	/* Compare second word */
-20:	ldw,ma	4(%r26), %r29
+20:	ldw	4(%r26), %r29
 	sub,=	%r29, %r23, %r0
 	b,n	cas2_end
 	/* Perform the store */

arch/parisc/kernel/time.c

View file

diff --git a/arch/parisc/kernel/time.c b/arch/parisc/kernel/time.c
index 2d956aa..8c0105a 100644
--- a/arch/parisc/kernel/time.c
+++ b/arch/parisc/kernel/time.c
@@ -253,7 +253,10 @@ static int __init init_cr16_clocksource(void)
 		cpu0_loc = per_cpu(cpu_data, 0).cpu_loc;
 
 		for_each_online_cpu(cpu) {
-			if (cpu0_loc == per_cpu(cpu_data, cpu).cpu_loc)
+			if (cpu == 0)
+				continue;
+			if ((cpu0_loc != 0) &&
+			    (cpu0_loc == per_cpu(cpu_data, cpu).cpu_loc))
 				continue;
 
 			clocksource_cr16.name = "cr16_unstable";