[PATCH] scsi: sym53c8xx_2: Fix WARN_ON in __sym_mfree_dma

[Tong Zhang]

This fix is similar to b36522150e5b. The WARN_ON is triggered due to
irq being disabled while dma_free_coherent expect it enabled.

[    1.501363] WARNING: CPU: 0 PID: 179 at kernel/dma/mapping.c:467 
dma_free_attrs+0x38/0x50
[    1.503940] RIP: 0010:dma_free_attrs+0x38/0x50
[    1.509138] Call Trace:
[    1.509273]  ___free_dma_mem_cluster+0x60/0x90 [sym53c8xx]
[    1.509570]  __sym_mfree+0xb2/0xd0 [sym53c8xx]
[    1.509811]  __sym_mfree_dma+0x65/0xa0 [sym53c8xx]
[    1.510070]  sym_hcb_free+0x8b/0x1e0 [sym53c8xx]
[    1.510320]  sym_free_resources+0x5c/0x7e [sym53c8xx]
[    1.510592]  sym2_probe.cold+0x3e3/0x555 [sym53c8xx]

Signed-off-by: Tong Zhang <ztong0...@gmail.com>
---
 drivers/scsi/sym53c8xx_2/sym_malloc.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/scsi/sym53c8xx_2/sym_malloc.c 
b/drivers/scsi/sym53c8xx_2/sym_malloc.c
index eb5c045c7c59..54ec7e7bf87f 100644
--- a/drivers/scsi/sym53c8xx_2/sym_malloc.c
+++ b/drivers/scsi/sym53c8xx_2/sym_malloc.c
@@ -321,20 +321,16 @@ void *__sym_calloc_dma(m_pool_ident_t dev_dmat, int size, 
char *name)
 
 void __sym_mfree_dma(m_pool_ident_t dev_dmat, void *m, int size, char *name)
 {
-       unsigned long flags;
        m_pool_p mp;
 
-       spin_lock_irqsave(&sym53c8xx_lock, flags);
        mp = ___get_dma_pool(dev_dmat);
        if (!mp)
-               goto out;
+               return;
        __sym_mfree(mp, m, size, name);
 #ifdef SYM_MEM_FREE_UNUSED
        if (!mp->nump)
                ___del_dma_pool(mp);
 #endif
- out:
-       spin_unlock_irqrestore(&sym53c8xx_lock, flags);
 }
 
 /*
-- 
2.25.1