tpm, tpm_tis: Avoid cache incoherency in test for interrupts
[ Upstream commit 858e8b79 ] The interrupt handler that sets the boolean variable irq_tested may run on another CPU as the thread that checks irq_tested as part of the irq test in tpm_tis_send(). Since nothing guarantees cache coherency between CPUs for unsynchronized accesses to boolean variables the testing thread might not perceive the value change done in the interrupt handler. Avoid this issue by setting the bit TPM_TIS_IRQ_TESTED in the flags field of the tpm_tis_data struct and by accessing this field with the bit manipulating functions that provide cache coherency. Also convert all other existing sites to use the proper macros when accessing this bitfield. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Michael Niewöhner <linux@mniewoehner.de> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Stable-dep-of: 1398aa80 ("tpm_tis: Use tpm_chip_{start,stop} decoration inside tpm_tis_resume") Signed-off-by: Sasha Levin <sashal@kernel.org>
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