5.4-stable patches

added patches:
	x86-alternatives-sync-core-before-enabling-interrupts.patch

diff --git a/queue-5.4/series b/queue-5.4/series
index b25a5d73b810bd31c705130017676078835d093b..9b4db0b70c27706eb4b61915c6e4fd7b5d5c0f17 100644 (file)
--- a/queue-5.4/series
+++ b/queue-5.4/series
@@ -38,3 +38,4 @@ usb-serial-option-add-quectel-rm500q-r13-firmware-support.patch
 bluetooth-hci_event-fix-not-checking-if-hci_op_inquiry-has-been-sent.patch
 net-9p-avoid-freeing-uninit-memory-in-p9pdu_vreadf.patch
 net-rfkill-gpio-set-gpio-direction.patch
+x86-alternatives-sync-core-before-enabling-interrupts.patch

diff --git a/queue-5.4/x86-alternatives-sync-core-before-enabling-interrupts.patch b/queue-5.4/x86-alternatives-sync-core-before-enabling-interrupts.patch
new file mode 100644 (file)
index 0000000..300097c
--- /dev/null
+++ b/queue-5.4/x86-alternatives-sync-core-before-enabling-interrupts.patch
@@ -0,0 +1,47 @@
+From 3ea1704a92967834bf0e64ca1205db4680d04048 Mon Sep 17 00:00:00 2001
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Thu, 7 Dec 2023 20:49:24 +0100
+Subject: x86/alternatives: Sync core before enabling interrupts
+
+From: Thomas Gleixner <tglx@linutronix.de>
+
+commit 3ea1704a92967834bf0e64ca1205db4680d04048 upstream.
+
+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 re-enabled 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.
+
+Fixes: 6fffacb30349 ("x86/alternatives, jumplabel: Use text_poke_early() before mm_init()")
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
+Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
+Cc: <stable@kernel.org>
+Link: https://lore.kernel.org/r/ZT6narvE%2BLxX%2B7Be@windriver.com
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/x86/kernel/alternative.c |    2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/arch/x86/kernel/alternative.c
++++ b/arch/x86/kernel/alternative.c
+@@ -772,8 +772,8 @@ void __init_or_module text_poke_early(vo
+       } else {
+               local_irq_save(flags);
+               memcpy(addr, opcode, len);
+-              local_irq_restore(flags);
+               sync_core();
++              local_irq_restore(flags);
+ 
+               /*
+                * Could also do a CLFLUSH here to speed up CPU recovery; but