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authorLinus Torvalds <torvalds@linux-foundation.org>2024-05-23 12:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2024-05-23 12:09:22 -0700
commit2b7ced108e93b837f152841ac1f0bf45ed2a6b21 (patch)
tree84ab89bc9f4b9aeea5aeb4cdda438333333b37d5 /arch/arm64/kernel/fpsimd.c
parent2ef32ad2241340565c35baf77fc95053c84eeeb0 (diff)
parente92bee9f861b466c676f0200be3e46af7bc4ac6b (diff)
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon: "The major fix here is for a filesystem corruption issue reported on Apple M1 as a result of buggy management of the floating point register state introduced in 6.8. I initially reverted one of the offending patches, but in the end Ard cooked a proper fix so there's a revert+reapply in the series. Aside from that, we've got some CPU errata workarounds and misc other fixes. - Fix broken FP register state tracking which resulted in filesystem corruption when dm-crypt is used - Workarounds for Arm CPU errata affecting the SSBS Spectre mitigation - Fix lockdep assertion in DMC620 memory controller PMU driver - Fix alignment of BUG table when CONFIG_DEBUG_BUGVERBOSE is disabled" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64/fpsimd: Avoid erroneous elide of user state reload Reapply "arm64: fpsimd: Implement lazy restore for kernel mode FPSIMD" arm64: asm-bug: Add .align 2 to the end of __BUG_ENTRY perf/arm-dmc620: Fix lockdep assert in ->event_init() Revert "arm64: fpsimd: Implement lazy restore for kernel mode FPSIMD" arm64: errata: Add workaround for Arm errata 3194386 and 3312417 arm64: cputype: Add Neoverse-V3 definitions arm64: cputype: Add Cortex-X4 definitions arm64: barrier: Restore spec_bar() macro
Diffstat (limited to 'arch/arm64/kernel/fpsimd.c')
-rw-r--r--arch/arm64/kernel/fpsimd.c44
1 files changed, 22 insertions, 22 deletions
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index ebb0158997ca..82e8a6017382 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -1535,6 +1535,27 @@ static void fpsimd_save_kernel_state(struct task_struct *task)
task->thread.kernel_fpsimd_cpu = smp_processor_id();
}
+/*
+ * Invalidate any task's FPSIMD state that is present on this cpu.
+ * The FPSIMD context should be acquired with get_cpu_fpsimd_context()
+ * before calling this function.
+ */
+static void fpsimd_flush_cpu_state(void)
+{
+ WARN_ON(!system_supports_fpsimd());
+ __this_cpu_write(fpsimd_last_state.st, NULL);
+
+ /*
+ * Leaving streaming mode enabled will cause issues for any kernel
+ * NEON and leaving streaming mode or ZA enabled may increase power
+ * consumption.
+ */
+ if (system_supports_sme())
+ sme_smstop();
+
+ set_thread_flag(TIF_FOREIGN_FPSTATE);
+}
+
void fpsimd_thread_switch(struct task_struct *next)
{
bool wrong_task, wrong_cpu;
@@ -1552,7 +1573,7 @@ void fpsimd_thread_switch(struct task_struct *next)
if (test_tsk_thread_flag(next, TIF_KERNEL_FPSTATE)) {
fpsimd_load_kernel_state(next);
- set_tsk_thread_flag(next, TIF_FOREIGN_FPSTATE);
+ fpsimd_flush_cpu_state();
} else {
/*
* Fix up TIF_FOREIGN_FPSTATE to correctly describe next's
@@ -1843,27 +1864,6 @@ void fpsimd_flush_task_state(struct task_struct *t)
}
/*
- * Invalidate any task's FPSIMD state that is present on this cpu.
- * The FPSIMD context should be acquired with get_cpu_fpsimd_context()
- * before calling this function.
- */
-static void fpsimd_flush_cpu_state(void)
-{
- WARN_ON(!system_supports_fpsimd());
- __this_cpu_write(fpsimd_last_state.st, NULL);
-
- /*
- * Leaving streaming mode enabled will cause issues for any kernel
- * NEON and leaving streaming mode or ZA enabled may increase power
- * consumption.
- */
- if (system_supports_sme())
- sme_smstop();
-
- set_thread_flag(TIF_FOREIGN_FPSTATE);
-}
-
-/*
* Save the FPSIMD state to memory and invalidate cpu view.
* This function must be called with preemption disabled.
*/