netdev - [PATCH] net: sun: cassini: Replace GFP_ATOMIC with GFP_KERNEL in cas_check

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Message-Id: <1523414079-2452-1-git-send-email-baijiaju1990@gmail.com>
Date:   Wed, 11 Apr 2018 10:34:39 +0800
From:   Jia-Ju Bai <baijiaju1990@...il.com>
To:     asun@...ksunrising.com
Cc:     netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        Jia-Ju Bai <baijiaju1990@...il.com>
Subject: [PATCH] net: sun: cassini: Replace GFP_ATOMIC with GFP_KERNEL in cas_check_invariants

cas_check_invariants() is never called in atomic context.

cas_check_invariants() is only called by cas_init_one(), which is 
only set as ".probe" in struct pci_driver.

Despite never getting called from atomic context,
cas_check_invariants() calls alloc_pages() with GFP_ATOMIC,
which does not sleep for allocation.
GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL,
which can sleep and improve the possibility of sucessful allocation.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@...il.com>
---
 drivers/net/ethernet/sun/cassini.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/sun/cassini.c b/drivers/net/ethernet/sun/cassini.c
index 382993c..4dd38e3 100644
--- a/drivers/net/ethernet/sun/cassini.c
+++ b/drivers/net/ethernet/sun/cassini.c
@@ -3412,7 +3412,7 @@ static int cas_check_invariants(struct cas *cp)
 #ifdef USE_PAGE_ORDER
 	if (PAGE_SHIFT < CAS_JUMBO_PAGE_SHIFT) {
 		/* see if we can allocate larger pages */
-		struct page *page = alloc_pages(GFP_ATOMIC,
+		struct page *page = alloc_pages(GFP_KERNEL,
 						CAS_JUMBO_PAGE_SHIFT -
 						PAGE_SHIFT);
 		if (page) {
-- 
1.9.1