From: Bruce Ashfield <[email protected]>
Integrating the following commit(s) to linux-yocto/6.5:
1/2 [
Author: Thomas Gleixner
Email: [email protected]
Subject: x86/alternatives: Sync core before enabling interrupts
Date: Thu, 7 Dec 2023 20:49:24 +0100
text_poke_early() does:
local_irq_save(flags);
memcpy(addr, opcode, len);
local_irq_restore(flags);
sync_core();
That's not really correct because the synchronization should happen before
interrupts are reenabled to ensure that a pending interrupt observes the
complete update of the opcodes.
It's not entirely clear whether the interrupt entry provides enough
serialization already, but moving the sync_core() invocation into interrupt
disabled region does no harm and is obviously correct.
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Bruce Ashfield <[email protected]>
]
2/2 [
Author: Thomas Gleixner
Email: [email protected]
Subject: x86/alternatives: Disable interrupts and sync when optimizing NOPs
in place
Date: Thu, 7 Dec 2023 20:49:26 +0100
apply_alternatives() treats alternatives with the ALT_FLAG_NOT flag set
special as it optimizes the existing NOPs in place.
Unfortunately this happens with interrupts enabled and does not provide any
form of core synchronization.
So an interrupt hitting in the middle of the update and using the affected
code path will observe a half updated NOP and crash and burn. The following
3 NOP sequence was observed to expose this crash halfways reliably under
QEMU 32bit:
0x90 0x90 0x90
which is replaced by the optimized 3 byte NOP:
0x8d 0x76 0x00
So an interrupt can observe:
1) 0x90 0x90 0x90 nop nop nop
2) 0x8d 0x90 0x90 undefined
3) 0x8d 0x76 0x90 lea -0x70(%esi),%esi
4) 0x8d 0x76 0x00 lea 0x0(%esi),%esi
Where only #1 and #4 are true NOPs. The same problem exists for 64bit
obviously.
Disable interrupts around this NOP optimization and invoke sync_core()
before reenabling them.
Fixes: 270a69c4485d ("x86/alternative: Support relocations in alternatives")
Reported-by: Paul Gortmaker <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Bruce Ashfield <[email protected]>
]
Signed-off-by: Bruce Ashfield <[email protected]>
Signed-off-by: Alexandre Belloni <[email protected]>
Signed-off-by: Richard Purdie <[email protected]>
(cherry picked from commit 1c8d29ab6b02c5b783429db3b67583deb1637142)
Signed-off-by: Steve Sakoman <[email protected]>
---
.../linux/linux-yocto-rt_6.5.bb | 2 +-
.../linux/linux-yocto-tiny_6.5.bb | 2 +-
meta/recipes-kernel/linux/linux-yocto_6.5.bb | 22 +++++++++----------
3 files changed, 13 insertions(+), 13 deletions(-)
diff --git a/meta/recipes-kernel/linux/linux-yocto-rt_6.5.bb
b/meta/recipes-kernel/linux/linux-yocto-rt_6.5.bb
index fccf0252d0..0120b9ba63 100644
--- a/meta/recipes-kernel/linux/linux-yocto-rt_6.5.bb
+++ b/meta/recipes-kernel/linux/linux-yocto-rt_6.5.bb
@@ -14,7 +14,7 @@ python () {
raise bb.parse.SkipRecipe("Set PREFERRED_PROVIDER_virtual/kernel to
linux-yocto-rt to enable it")
}
-SRCREV_machine ?= "1d89cd73350cad73ecf330ad3785e6d8bdec092d"
+SRCREV_machine ?= "3ad8578bcc3186cde9b35de8c56afc0cba68bc55"
SRCREV_meta ?= "3b1f87ec237ec3ad9acffb3d75c55efe958085dc"
SRC_URI =
"git://git.yoctoproject.org/linux-yocto.git;branch=${KBRANCH};name=machine;protocol=https
\
diff --git a/meta/recipes-kernel/linux/linux-yocto-tiny_6.5.bb
b/meta/recipes-kernel/linux/linux-yocto-tiny_6.5.bb
index b63d5ad893..cc24e3d346 100644
--- a/meta/recipes-kernel/linux/linux-yocto-tiny_6.5.bb
+++ b/meta/recipes-kernel/linux/linux-yocto-tiny_6.5.bb
@@ -17,7 +17,7 @@ DEPENDS += "openssl-native util-linux-native"
KMETA = "kernel-meta"
KCONF_BSP_AUDIT_LEVEL = "2"
-SRCREV_machine ?= "95753fe2a7d507646224fe973e2a4fc48cb7694d"
+SRCREV_machine ?= "fc3138c70652b48a0bf3620fd7aa861fa1f14e27"
SRCREV_meta ?= "3b1f87ec237ec3ad9acffb3d75c55efe958085dc"
PV = "${LINUX_VERSION}+git"
diff --git a/meta/recipes-kernel/linux/linux-yocto_6.5.bb
b/meta/recipes-kernel/linux/linux-yocto_6.5.bb
index 984940d24c..e7abc9784a 100644
--- a/meta/recipes-kernel/linux/linux-yocto_6.5.bb
+++ b/meta/recipes-kernel/linux/linux-yocto_6.5.bb
@@ -18,17 +18,17 @@ KBRANCH:qemux86-64 ?= "v6.5/standard/base"
KBRANCH:qemuloongarch64 ?= "v6.5/standard/base"
KBRANCH:qemumips64 ?= "v6.5/standard/mti-malta64"
-SRCREV_machine:qemuarm ?= "3fdf15eaa1db1b6fd1de804d03c6b4a10c2c3f4b"
-SRCREV_machine:qemuarm64 ?= "70210986a1c554098fb6f75f6cd10ab85171506a"
-SRCREV_machine:qemuloongarch64 ?= "7fe59b2e3f40a94ce4477854264e219aeb972990"
-SRCREV_machine:qemumips ?= "338cee0966e9ea856a696df0a9f5432f74b06270"
-SRCREV_machine:qemuppc ?= "2fbe7b92bda7afe7aca6e58b0ac124f2a26737ee"
-SRCREV_machine:qemuriscv64 ?= "7fe59b2e3f40a94ce4477854264e219aeb972990"
-SRCREV_machine:qemuriscv32 ?= "7fe59b2e3f40a94ce4477854264e219aeb972990"
-SRCREV_machine:qemux86 ?= "7fe59b2e3f40a94ce4477854264e219aeb972990"
-SRCREV_machine:qemux86-64 ?= "7fe59b2e3f40a94ce4477854264e219aeb972990"
-SRCREV_machine:qemumips64 ?= "ff5efc72e961cf345f935ac14cdcaa9843ec5b23"
-SRCREV_machine ?= "7fe59b2e3f40a94ce4477854264e219aeb972990"
+SRCREV_machine:qemuarm ?= "07ca2c1cc013343f9a47b5ac4f37ed60f66fd73b"
+SRCREV_machine:qemuarm64 ?= "7af45f35fdcc82bbff07fa3d031620d5f5728b6b"
+SRCREV_machine:qemuloongarch64 ?= "e53dc7514de7d2fbe0f80547a50c0542928e2d11"
+SRCREV_machine:qemumips ?= "e0b08aab2ccc4257f0b34e7dcb1e054ea188a43d"
+SRCREV_machine:qemuppc ?= "9e609ca17604c708fdc6e7e5c9355bb2c5b73bcd"
+SRCREV_machine:qemuriscv64 ?= "e53dc7514de7d2fbe0f80547a50c0542928e2d11"
+SRCREV_machine:qemuriscv32 ?= "e53dc7514de7d2fbe0f80547a50c0542928e2d11"
+SRCREV_machine:qemux86 ?= "e53dc7514de7d2fbe0f80547a50c0542928e2d11"
+SRCREV_machine:qemux86-64 ?= "e53dc7514de7d2fbe0f80547a50c0542928e2d11"
+SRCREV_machine:qemumips64 ?= "58ffd9a4a907262daaedd9aca1e95e65d9716de3"
+SRCREV_machine ?= "e53dc7514de7d2fbe0f80547a50c0542928e2d11"
SRCREV_meta ?= "3b1f87ec237ec3ad9acffb3d75c55efe958085dc"
# set your preferred provider of linux-yocto to 'linux-yocto-upstream', and
you'll
--
2.34.1
-=-=-=-=-=-=-=-=-=-=-=-
Links: You receive all messages sent to this group.
View/Reply Online (#193031):
https://lists.openembedded.org/g/openembedded-core/message/193031
Mute This Topic: https://lists.openembedded.org/mt/103418333/21656
Group Owner: [email protected]
Unsubscribe: https://lists.openembedded.org/g/openembedded-core/unsub
[[email protected]]
-=-=-=-=-=-=-=-=-=-=-=-
