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Commit2997876c4a("powerpc/32: Restore clearing of MSR[RI] at interrupt/syscall exit") delayed clearing of MSR[RI], but missed that both MSR[RI] and MSR[EE] are cleared at the same time, so the commit also delayed the disabling of interrupts, leading to unexpected behaviour. To fix that, mostly revert the blamed commit and restore the clearing of MSR[RI] in interrupt_exit_kernel_prepare() instead. For 8xx it implies adding a synchronising instruction after the mtspr in order to make sure no instruction counter interrupt (used for perf events) will fire just after clearing MSR[RI]. Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de> Closes: https://lore.kernel.org/all/4d0bd05d-6158-1323-3509-744d3fbe8fc7@xenosoft.de/ Reported-by: Guenter Roeck <linux@roeck-us.net> Closes: https://lore.kernel.org/all/6b05eb1c-fdef-44e0-91a7-8286825e68f1@roeck-us.net/ Fixes:2997876c4a("powerpc/32: Restore clearing of MSR[RI] at interrupt/syscall exit") Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/585ea521b2be99d293b539bbfae148366cfb3687.1766146895.git.chleroy@kernel.org