From 8a1e97ee2e025f116765c92409a3cf8f6cb07ad6 Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Thu, 29 Mar 2007 23:42:42 +0100 Subject: [MIPS] SMTC: Fix recursion in instant IPI replay code. local_irq_restore -> raw_local_irq_restore -> irq_restore_epilog -> smtc_ipi_replay -> smtc_ipi_dq -> spin_unlock_irqrestore -> _spin_unlock_irqrestore -> local_irq_restore The recursion does abort when there is no more IPI queued for a CPU, so this isn't usually fatal which is why we got away with this for so long until this was discovered by code inspection. Signed-off-by: Ralf Baechle --- include/asm-mips/smtc_ipi.h | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) (limited to 'include/asm-mips/smtc_ipi.h') diff --git a/include/asm-mips/smtc_ipi.h b/include/asm-mips/smtc_ipi.h index 360ea6d250c..a52a4a7a36e 100644 --- a/include/asm-mips/smtc_ipi.h +++ b/include/asm-mips/smtc_ipi.h @@ -65,12 +65,10 @@ static inline void smtc_ipi_nq(struct smtc_ipi_q *q, struct smtc_ipi *p) spin_unlock_irqrestore(&q->lock, flags); } -static inline struct smtc_ipi *smtc_ipi_dq(struct smtc_ipi_q *q) +static inline struct smtc_ipi *__smtc_ipi_dq(struct smtc_ipi_q *q) { struct smtc_ipi *p; - long flags; - spin_lock_irqsave(&q->lock, flags); if (q->head == NULL) p = NULL; else { @@ -81,7 +79,19 @@ static inline struct smtc_ipi *smtc_ipi_dq(struct smtc_ipi_q *q) if (q->head == NULL) q->tail = NULL; } + + return p; +} + +static inline struct smtc_ipi *smtc_ipi_dq(struct smtc_ipi_q *q) +{ + unsigned long flags; + struct smtc_ipi *p; + + spin_lock_irqsave(&q->lock, flags); + p = __smtc_ipi_dq(q); spin_unlock_irqrestore(&q->lock, flags); + return p; } -- cgit v1.2.3