Daniel Thompson 9a0c994191 arm64: cacheflush: Fix KGDB trap detection ... [ Upstream commit ab8ad279ceac4fc78ae4dcf1a26326e05695e537 ] flush_icache_range() contains a bodge to avoid issuing IPIs when the kgdb trap handler is running because issuing IPIs is unsafe (and not needed) in this execution context. However the current test, based on kgdb_connected is flawed: it both over-matches and under-matches. The over match occurs because kgdb_connected is set when gdb attaches to the stub and remains set during normal running. This is relatively harmelss because in almost all cases irq_disabled() will be false. The under match is more serious. When kdb is used instead of kgdb to access the debugger then kgdb_connected is not set in all the places that the debug core updates sw breakpoints (and hence flushes the icache). This can lead to deadlock. Fix by replacing the ad-hoc check with the proper kgdb macro. This also allows us to drop the #ifdef wrapper. Fixes: 3b8c9f1cdf ("arm64: IPI each CPU after invalidating the I-cache for kernel mappings") Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20200504170518.2959478-1-daniel.thompson@linaro.org Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-06-22 09:30:52 +02:00
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asm	arm64: cacheflush: Fix KGDB trap detection	2020-06-22 09:30:52 +02:00
uapi/asm	KVM: arm64: Correct PSTATE on exception entry	2020-02-11 04:35:16 -08:00