Commit 51915c6d authored by James Clarke's avatar James Clarke Committed by Greg Kroah-Hartman

sparc: Handle negative offsets in arch_jump_label_transform

[ Upstream commit 9d9fa230 ]

Additionally, if the offset will overflow the immediate for a ba,pt
instruction, fall back on a standard ba to get an extra 3 bits.
Signed-off-by: default avatarJames Clarke <jrtc27@jrtc27.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent da6fe239
......@@ -13,19 +13,30 @@
void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
u32 val;
u32 *insn = (u32 *) (unsigned long) entry->code;
u32 val;
if (type == JUMP_LABEL_JMP) {
s32 off = (s32)entry->target - (s32)entry->code;
bool use_v9_branch = false;
BUG_ON(off & 3);
#ifdef CONFIG_SPARC64
/* ba,pt %xcc, . + (off << 2) */
val = 0x10680000 | ((u32) off >> 2);
#else
/* ba . + (off << 2) */
val = 0x10800000 | ((u32) off >> 2);
if (off <= 0xfffff && off >= -0x100000)
use_v9_branch = true;
#endif
if (use_v9_branch) {
/* WDISP19 - target is . + immed << 2 */
/* ba,pt %xcc, . + off */
val = 0x10680000 | (((u32) off >> 2) & 0x7ffff);
} else {
/* WDISP22 - target is . + immed << 2 */
BUG_ON(off > 0x7fffff);
BUG_ON(off < -0x800000);
/* ba . + off */
val = 0x10800000 | (((u32) off >> 2) & 0x3fffff);
}
} else {
val = 0x01000000;
}
......
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