Merge remote-tracking branch 'net-next/master' into mac80211-next

Bring in net-next which had pulled in net, so I have the changes
from mac80211 and can apply a patch that would otherwise conflict.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 22 insertions, 29 deletions

diff --git a/arch/s390/kernel/nospec-branch.c b/arch/s390/kernel/nospec-branch.c
index 14867ec5f726..8ad6a7128b3a 100644
--- a/arch/s390/kernel/nospec-branch.c
+++ b/arch/s390/kernel/nospec-branch.c
@@ -43,24 +43,6 @@ static int __init nospec_report(void)
 }
 arch_initcall(nospec_report);
 
-#ifdef CONFIG_SYSFS
-ssize_t cpu_show_spectre_v1(struct device *dev,
-			    struct device_attribute *attr, char *buf)
-{
-	return sprintf(buf, "Mitigation: __user pointer sanitization\n");
-}
-
-ssize_t cpu_show_spectre_v2(struct device *dev,
-			    struct device_attribute *attr, char *buf)
-{
-	if (IS_ENABLED(CC_USING_EXPOLINE) && !nospec_disable)
-		return sprintf(buf, "Mitigation: execute trampolines\n");
-	if (__test_facility(82, S390_lowcore.alt_stfle_fac_list))
-		return sprintf(buf, "Mitigation: limited branch prediction.\n");
-	return sprintf(buf, "Vulnerable\n");
-}
-#endif
-
 #ifdef CONFIG_EXPOLINE
 
 int nospec_disable = IS_ENABLED(CONFIG_EXPOLINE_OFF);
@@ -72,7 +54,7 @@ static int __init nospectre_v2_setup_early(char *str)
 }
 early_param("nospectre_v2", nospectre_v2_setup_early);
 
-static int __init spectre_v2_auto_early(void)
+void __init nospec_auto_detect(void)
 {
 	if (IS_ENABLED(CC_USING_EXPOLINE)) {
 		/*
@@ -87,11 +69,7 @@ static int __init spectre_v2_auto_early(void)
 	 * nobp setting decides what is done, this depends on the
 	 * CONFIG_KERNEL_NP option and the nobp/nospec parameters.
 	 */
-	return 0;
 }
-#ifdef CONFIG_EXPOLINE_AUTO
-early_initcall(spectre_v2_auto_early);
-#endif
 
 static int __init spectre_v2_setup_early(char *str)
 {
@@ -102,7 +80,7 @@ static int __init spectre_v2_setup_early(char *str)
 	if (str && !strncmp(str, "off", 3))
 		nospec_disable = 1;
 	if (str && !strncmp(str, "auto", 4))
-		spectre_v2_auto_early();
+		nospec_auto_detect();
 	return 0;
 }
 early_param("spectre_v2", spectre_v2_setup_early);
@@ -115,7 +93,6 @@ static void __init_or_module __nospec_revert(s32 *start, s32 *end)
 	s32 *epo;
 
 	/* Second part of the instruction replace is always a nop */
-	memcpy(insnbuf + 2, (char[]) { 0x47, 0x00, 0x00, 0x00 }, 4);
 	for (epo = start; epo < end; epo++) {
 		instr = (u8 *) epo + *epo;
 		if (instr[0] == 0xc0 && (instr[1] & 0x0f) == 0x04)
@@ -136,18 +113,34 @@ static void __init_or_module __nospec_revert(s32 *start, s32 *end)
 			br = thunk + (*(int *)(thunk + 2)) * 2;
 		else
 			continue;
-		if (br[0] != 0x07 || (br[1] & 0xf0) != 0xf0)
+		/* Check for unconditional branch 0x07f? or 0x47f???? */
+		if ((br[0] & 0xbf) != 0x07 || (br[1] & 0xf0) != 0xf0)
 			continue;
+
+		memcpy(insnbuf + 2, (char[]) { 0x47, 0x00, 0x07, 0x00 }, 4);
 		switch (type) {
 		case BRCL_EXPOLINE:
-			/* brcl to thunk, replace with br + nop */
 			insnbuf[0] = br[0];
 			insnbuf[1] = (instr[1] & 0xf0) | (br[1] & 0x0f);
+			if (br[0] == 0x47) {
+				/* brcl to b, replace with bc + nopr */
+				insnbuf[2] = br[2];
+				insnbuf[3] = br[3];
+			} else {
+				/* brcl to br, replace with bcr + nop */
+			}
 			break;
 		case BRASL_EXPOLINE:
-			/* brasl to thunk, replace with basr + nop */
-			insnbuf[0] = 0x0d;
 			insnbuf[1] = (instr[1] & 0xf0) | (br[1] & 0x0f);
+			if (br[0] == 0x47) {
+				/* brasl to b, replace with bas + nopr */
+				insnbuf[0] = 0x4d;
+				insnbuf[2] = br[2];
+				insnbuf[3] = br[3];
+			} else {
+				/* brasl to br, replace with basr + nop */
+				insnbuf[0] = 0x0d;
+			}
 			break;
 		}