diff options
Diffstat (limited to 'meta/recipes-devtools/qemu')
-rw-r--r-- | meta/recipes-devtools/qemu/qemu/0001-arm-translate-a64-treat-DISAS_UPDATE-as-variant-of-D.patch | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/meta/recipes-devtools/qemu/qemu/0001-arm-translate-a64-treat-DISAS_UPDATE-as-variant-of-D.patch b/meta/recipes-devtools/qemu/qemu/0001-arm-translate-a64-treat-DISAS_UPDATE-as-variant-of-D.patch new file mode 100644 index 0000000000..f90cae694c --- /dev/null +++ b/meta/recipes-devtools/qemu/qemu/0001-arm-translate-a64-treat-DISAS_UPDATE-as-variant-of-D.patch @@ -0,0 +1,67 @@ +From a75a52d62418dafe462be4fe30485501d1010bb9 Mon Sep 17 00:00:00 2001 +From: Victor Kamensky <kamensky@cisco.com> +Date: Fri, 23 Mar 2018 18:26:45 +0000 +Subject: [PATCH] arm/translate-a64: treat DISAS_UPDATE as variant of + DISAS_EXIT +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +In OE project 4.15 linux kernel boot hang was observed under +single cpu aarch64 qemu. Kernel code was in a loop waiting for +vtimer arrival, spinning in TC generated blocks, while interrupt +was pending unprocessed. This happened because when qemu tried to +handle vtimer interrupt target had interrupts disabled, as +result flag indicating TCG exit, cpu->icount_decr.u16.high, +was cleared but arm_cpu_exec_interrupt function did not call +arm_cpu_do_interrupt to process interrupt. Later when target +reenabled interrupts, it happened without exit into main loop, so +following code that waited for result of interrupt execution +run in infinite loop. + +To solve the problem instructions that operate on CPU sys state +(i.e enable/disable interrupt), and marked as DISAS_UPDATE, +should be considered as DISAS_EXIT variant, and should be +forced to exit back to main loop so qemu will have a chance +processing pending CPU state updates, including pending +interrupts. + +This change brings consistency with how DISAS_UPDATE is treated +in aarch32 case. + +CC: Peter Maydell <peter.maydell@linaro.org> +CC: Alex Bennée <alex.bennee@linaro.org> +CC: qemu-stable@nongnu.org +Suggested-by: Peter Maydell <peter.maydell@linaro.org> +Signed-off-by: Victor Kamensky <kamensky@cisco.com> +Reviewed-by: Richard Henderson <richard.henderson@linaro.org> +Message-id: 1521526368-1996-1-git-send-email-kamensky@cisco.com +Signed-off-by: Peter Maydell <peter.maydell@linaro.org> +Upstream-Status: Backport +--- + target/arm/translate-a64.c | 6 +++--- + 1 file changed, 3 insertions(+), 3 deletions(-) + +diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c +index 31ff047..327513e 100644 +--- a/target/arm/translate-a64.c ++++ b/target/arm/translate-a64.c +@@ -13378,12 +13378,12 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu) + case DISAS_UPDATE: + gen_a64_set_pc_im(dc->pc); + /* fall through */ +- case DISAS_JUMP: +- tcg_gen_lookup_and_goto_ptr(); +- break; + case DISAS_EXIT: + tcg_gen_exit_tb(0); + break; ++ case DISAS_JUMP: ++ tcg_gen_lookup_and_goto_ptr(); ++ break; + case DISAS_NORETURN: + case DISAS_SWI: + break; +-- +2.7.4 + |