x86/process: Make room for TIF_SPEC_L1D_FLUSH

The upcoming support for paranoid L1D flush in switch_mm() requires that
TIF_SPEC_IB and the new TIF_SPEC_L1D_FLUSH are two consecutive bits in
thread_info::flags.

Move TIF_SPEC_FORCE_UPDATE to a spare bit to make room for the new one.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Balbir Singh <sblbir@amazon.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210108121056.21940-1-sblbir@amazon.com

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index de406d9..d9afd35 100644 (file)
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -81,7 +81,6 @@ struct thread_info {
 #define TIF_SINGLESTEP         4       /* reenable singlestep on user return*/
 #define TIF_SSBD               5       /* Speculative store bypass disable */
 #define TIF_SPEC_IB            9       /* Indirect branch speculation mitigation */
-#define TIF_SPEC_FORCE_UPDATE  10      /* Force speculation MSR update in context switch */
 #define TIF_USER_RETURN_NOTIFY 11      /* notify kernel of userspace return */
 #define TIF_UPROBE             12      /* breakpointed or singlestepping */
 #define TIF_PATCH_PENDING      13      /* pending live patching update */
@@ -93,6 +92,7 @@ struct thread_info {
 #define TIF_MEMDIE             20      /* is terminating due to OOM killer */
 #define TIF_POLLING_NRFLAG     21      /* idle is polling for TIF_NEED_RESCHED */
 #define TIF_IO_BITMAP          22      /* uses I/O bitmap */
+#define TIF_SPEC_FORCE_UPDATE  23      /* Force speculation MSR update in context switch */
 #define TIF_FORCED_TF          24      /* true if TF in eflags artificially */
 #define TIF_BLOCKSTEP          25      /* set when we want DEBUGCTLMSR_BTF */
 #define TIF_LAZY_MMU_UPDATES   27      /* task is updating the mmu lazily */
@@ -104,7 +104,6 @@ struct thread_info {
 #define _TIF_SINGLESTEP                (1 << TIF_SINGLESTEP)
 #define _TIF_SSBD              (1 << TIF_SSBD)
 #define _TIF_SPEC_IB           (1 << TIF_SPEC_IB)
-#define _TIF_SPEC_FORCE_UPDATE (1 << TIF_SPEC_FORCE_UPDATE)
 #define _TIF_USER_RETURN_NOTIFY        (1 << TIF_USER_RETURN_NOTIFY)
 #define _TIF_UPROBE            (1 << TIF_UPROBE)
 #define _TIF_PATCH_PENDING     (1 << TIF_PATCH_PENDING)
@@ -115,6 +114,7 @@ struct thread_info {
 #define _TIF_SLD               (1 << TIF_SLD)
 #define _TIF_POLLING_NRFLAG    (1 << TIF_POLLING_NRFLAG)
 #define _TIF_IO_BITMAP         (1 << TIF_IO_BITMAP)
+#define _TIF_SPEC_FORCE_UPDATE (1 << TIF_SPEC_FORCE_UPDATE)
 #define _TIF_FORCED_TF         (1 << TIF_FORCED_TF)
 #define _TIF_BLOCKSTEP         (1 << TIF_BLOCKSTEP)
 #define _TIF_LAZY_MMU_UPDATES  (1 << TIF_LAZY_MMU_UPDATES)