hgafb: resource management fix

Release ports which are requested during detection which are not freed if
there is no hga card.  Otherwise there is a crash during cat /proc/ioports
command.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/video/hgafb.c b/drivers/video/hgafb.c
index fb9e672..c18880d 100644 (file)
--- a/drivers/video/hgafb.c
+++ b/drivers/video/hgafb.c
@@ -279,7 +279,7 @@ static void hga_blank(int blank_mode)
 
 static int __init hga_card_detect(void)
 {
-       int count=0;
+       int count = 0;
        void __iomem *p, *q;
        unsigned short p_save, q_save;
 
@@ -303,20 +303,18 @@ static int __init hga_card_detect(void)
        writew(0x55aa, p); if (readw(p) == 0x55aa) count++;
        writew(p_save, p);
 
-       if (count != 2) {
-               return 0;
-       }
+       if (count != 2)
+               goto error;
 
        /* Ok, there is definitely a card registering at the correct
         * memory location, so now we do an I/O port test.
         */
        
-       if (!test_hga_b(0x66, 0x0f)) {      /* cursor low register */
-               return 0;
-       }
-       if (!test_hga_b(0x99, 0x0f)) {     /* cursor low register */
-               return 0;
-       }
+       if (!test_hga_b(0x66, 0x0f))        /* cursor low register */
+               goto error;
+
+       if (!test_hga_b(0x99, 0x0f))     /* cursor low register */
+               goto error;
 
        /* See if the card is a Hercules, by checking whether the vsync
         * bit of the status register is changing.  This test lasts for
@@ -331,7 +329,7 @@ static int __init hga_card_detect(void)
        }
 
        if (p_save == q_save) 
-               return 0;
+               goto error;
 
        switch (inb_p(HGA_STATUS_PORT) & 0x70) {
                case 0x10:
@@ -348,6 +346,12 @@ static int __init hga_card_detect(void)
                        break;
        }
        return 1;
+error:
+       if (release_io_ports)
+               release_region(0x3b0, 12);
+       if (release_io_port)
+               release_region(0x3bf, 1);
+       return 0;
 }
 
 /**