Commit a1259dd8 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Catalin Marinas
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arm64/sve: Delay freeing memory in fpsimd_flush_thread() 



fpsimd_flush_thread() invokes kfree() via sve_free()+sme_free() within a
preempt disabled section which is not working on -RT.

Delay freeing of memory until preemption is enabled again.

Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: default avatarMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220505163207.85751-2-bigeasy@linutronix.de


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent d158a060

arch/arm64/kernel/fpsimd.c

+15 −2
Original line number Diff line number Diff line
@@ -1562,6 +1562,9 @@ static void fpsimd_flush_thread_vl(enum vec_type type) 


void fpsimd_flush_thread(void)

{

	void *sve_state = NULL;

	void *za_state = NULL;



	if (!system_supports_fpsimd())

		return;
@@ -1573,18 +1576,28 @@ void fpsimd_flush_thread(void) 


	if (system_supports_sve()) {

		clear_thread_flag(TIF_SVE);

		sve_free(current);



		/* Defer kfree() while in atomic context */

		sve_state = current->thread.sve_state;

		current->thread.sve_state = NULL;



		fpsimd_flush_thread_vl(ARM64_VEC_SVE);

	}



	if (system_supports_sme()) {

		clear_thread_flag(TIF_SME);

		sme_free(current);



		/* Defer kfree() while in atomic context */

		za_state = current->thread.za_state;

		current->thread.za_state = NULL;



		fpsimd_flush_thread_vl(ARM64_VEC_SME);

		current->thread.svcr = 0;

	}



	put_cpu_fpsimd_context();

	kfree(sve_state);

	kfree(za_state);

}



/*