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pcim_intx() tries to restore the INTx bit at removal via devres, but there is a chance that it restores a wrong value. Because the value to be restored is blindly assumed to be the negative of the enable argument, when a driver calls pcim_intx() unnecessarily for the already enabled state, it'll restore to the disabled state in turn. That is, the function assumes the case like: // INTx == 1 pcim_intx(pdev, 0); // old INTx value assumed to be 1 -> correct but it might be like the following, too: // INTx == 0 pcim_intx(pdev, 0); // old INTx value assumed to be 1 -> wrong Also, when a driver calls pcim_intx() multiple times with different enable argument values, the last one will win no matter what value it is. This can lead to inconsistency, e.g. // INTx == 1 pcim_intx(pdev, 0); // OK ... pcim_intx(pdev, 1); // now old INTx wrongly assumed to be 0 This patch addresses those inconsistencies by saving the original INTx state at the first pcim_intx() call. For that, get_or_create_intx_devres() is folded into pcim_intx() caller side; it allows us to simply check the already allocated devres and record the original INTx along with the devres_alloc() call. Link: https://lore.kernel.org/r/20241031134300.10296-1-tiwai@suse.de Fixes: 25216afc9db5 ("PCI: Add managed pcim_intx()") Link: https://lore.kernel.org/87v7xk2ps5.wl-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Philipp Stanner <pstanner@redhat.com> Cc: stable@vger.kernel.org # v6.11+