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authorLinus Torvalds <torvalds@linux-foundation.org>2020-04-09 11:01:42 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-04-09 11:01:42 -0700
commite4da01d8333e500e15a674d75885a9dfcfd31e77 (patch)
tree4a9816c19bde1b027c58aa2486535221d4c355b9 /arch/powerpc/kernel/time.c
parent6cff4821c0856cbf310601c849047fbd666216ea (diff)
parent6ba4a2d3591039aea1cb45c7c42262d26351a2fa (diff)
Merge tag 'powerpc-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull more powerpc updates from Michael Ellerman: "The bulk of this is the series to make CONFIG_COMPAT user-selectable, it's been around for a long time but was blocked behind the syscall-in-C series. Plus there's also a few fixes and other minor things. Summary: - A fix for a crash in machine check handling on pseries (ie. guests) - A small series to make it possible to disable CONFIG_COMPAT, and turn it off by default for ppc64le where it's not used. - A few other miscellaneous fixes and small improvements. Thanks to: Alexey Kardashevskiy, Anju T Sudhakar, Arnd Bergmann, Christophe Leroy, Dan Carpenter, Ganesh Goudar, Geert Uytterhoeven, Geoff Levand, Mahesh Salgaonkar, Markus Elfring, Michal Suchanek, Nicholas Piggin, Stephen Boyd, Wen Xiong" * tag 'powerpc-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: selftests/powerpc: Always build the tm-poison test 64-bit powerpc: Improve ppc_save_regs() Revert "powerpc/64: irq_work avoid interrupt when called with hardware irqs enabled" powerpc/time: Replace <linux/clk-provider.h> by <linux/of_clk.h> powerpc/pseries/ddw: Extend upper limit for huge DMA window for persistent memory powerpc/perf: split callchain.c by bitness powerpc/64: Make COMPAT user-selectable disabled on littleendian by default. powerpc/64: make buildable without CONFIG_COMPAT powerpc/perf: consolidate valid_user_sp -> invalid_user_sp powerpc/perf: consolidate read_user_stack_32 powerpc: move common register copy functions from signal_32.c to signal.c powerpc: Add back __ARCH_WANT_SYS_LLSEEK macro powerpc/ps3: Set CONFIG_UEVENT_HELPER=y in ps3_defconfig powerpc/ps3: Remove an unneeded NULL check powerpc/ps3: Remove duplicate error message powerpc/powernv: Re-enable imc trace-mode in kernel powerpc/perf: Implement a global lock to avoid races between trace, core and thread imc events. powerpc/pseries: Fix MCE handling on pseries selftests/eeh: Skip ahci adapters powerpc/64s: Fix doorbell wakeup msgclr optimisation
Diffstat (limited to 'arch/powerpc/kernel/time.c')
-rw-r--r--arch/powerpc/kernel/time.c48
1 files changed, 14 insertions, 34 deletions
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index bda9cb4a0a5f..6fcae436ae51 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -50,7 +50,7 @@
#include <linux/irq.h>
#include <linux/delay.h>
#include <linux/irq_work.h>
-#include <linux/clk-provider.h>
+#include <linux/of_clk.h>
#include <linux/suspend.h>
#include <linux/sched/cputime.h>
#include <linux/processor.h>
@@ -522,35 +522,6 @@ static inline void clear_irq_work_pending(void)
"i" (offsetof(struct paca_struct, irq_work_pending)));
}
-void arch_irq_work_raise(void)
-{
- preempt_disable();
- set_irq_work_pending_flag();
- /*
- * Non-nmi code running with interrupts disabled will replay
- * irq_happened before it re-enables interrupts, so setthe
- * decrementer there instead of causing a hardware exception
- * which would immediately hit the masked interrupt handler
- * and have the net effect of setting the decrementer in
- * irq_happened.
- *
- * NMI interrupts can not check this when they return, so the
- * decrementer hardware exception is raised, which will fire
- * when interrupts are next enabled.
- *
- * BookE does not support this yet, it must audit all NMI
- * interrupt handlers to ensure they call nmi_enter() so this
- * check would be correct.
- */
- if (IS_ENABLED(CONFIG_BOOKE) || !irqs_disabled() || in_nmi()) {
- set_dec(1);
- } else {
- hard_irq_disable();
- local_paca->irq_happened |= PACA_IRQ_DEC;
- }
- preempt_enable();
-}
-
#else /* 32-bit */
DEFINE_PER_CPU(u8, irq_work_pending);
@@ -559,16 +530,27 @@ DEFINE_PER_CPU(u8, irq_work_pending);
#define test_irq_work_pending() __this_cpu_read(irq_work_pending)
#define clear_irq_work_pending() __this_cpu_write(irq_work_pending, 0)
+#endif /* 32 vs 64 bit */
+
void arch_irq_work_raise(void)
{
+ /*
+ * 64-bit code that uses irq soft-mask can just cause an immediate
+ * interrupt here that gets soft masked, if this is called under
+ * local_irq_disable(). It might be possible to prevent that happening
+ * by noticing interrupts are disabled and setting decrementer pending
+ * to be replayed when irqs are enabled. The problem there is that
+ * tracing can call irq_work_raise, including in code that does low
+ * level manipulations of irq soft-mask state (e.g., trace_hardirqs_on)
+ * which could get tangled up if we're messing with the same state
+ * here.
+ */
preempt_disable();
set_irq_work_pending_flag();
set_dec(1);
preempt_enable();
}
-#endif /* 32 vs 64 bit */
-
#else /* CONFIG_IRQ_WORK */
#define test_irq_work_pending() 0
@@ -1149,9 +1131,7 @@ void __init time_init(void)
init_decrementer_clockevent();
tick_setup_hrtimer_broadcast();
-#ifdef CONFIG_COMMON_CLK
of_clk_init(NULL);
-#endif
}
/*