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https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
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a98ce5c6fe
As it is some callers of synchronize_irq rely on memory barriers to provide synchronisation against the IRQ handlers. For example, the tg3 driver does tp->irq_sync = 1; smp_mb(); synchronize_irq(); and then in the IRQ handler: if (!tp->irq_sync) netif_rx_schedule(dev, &tp->napi); Unfortunately memory barriers only work well when they come in pairs. Because we don't actually have memory barriers on the IRQ path, the memory barrier before the synchronize_irq() doesn't actually protect us. In particular, synchronize_irq() may return followed by the result of netif_rx_schedule being made visible. This patch (mostly written by Linus) fixes this by using spin locks instead of memory barries on the synchronize_irq() path. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| autoprobe.c | ||
| chip.c | ||
| devres.c | ||
| handle.c | ||
| internals.h | ||
| Makefile | ||
| manage.c | ||
| migration.c | ||
| proc.c | ||
| resend.c | ||
| spurious.c | ||