# git rev-parse -q --verify 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479^{commit} # git fetch -q -n -f git://gitlab.ozlabs.ibm.com/linuxppc/linux.git next-test warning: The last gc run reported the following. Please correct the root cause and remove .git/gc.log. Automatic cleanup will not be performed until the file is removed. warning: There are too many unreachable loose objects; run 'git prune' to remove them. # git rev-parse -q --verify 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479^{commit} 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479 # git checkout -q -f -B kisskb 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479 # git clean -qxdf # < git log -1 # commit 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479 # Author: Suraj Jitindar Singh # Date: Thu Jun 20 11:46:51 2019 +1000 # # KVM: PPC: Book3S HV: Clear pending decrementer exceptions on nested guest entry # # If we enter an L1 guest with a pending decrementer exception then this # is cleared on guest exit if the guest has writtien a positive value # into the decrementer (indicating that it handled the decrementer # exception) since there is no other way to detect that the guest has # handled the pending exception and that it should be dequeued. In the # event that the L1 guest tries to run a nested (L2) guest immediately # after this and the L2 guest decrementer is negative (which is loaded # by L1 before making the H_ENTER_NESTED hcall), then the pending # decrementer exception isn't cleared and the L2 entry is blocked since # L1 has a pending exception, even though L1 may have already handled # the exception and written a positive value for it's decrementer. This # results in a loop of L1 trying to enter the L2 guest and L0 blocking # the entry since L1 has an interrupt pending with the outcome being # that L2 never gets to run and hangs. # # Fix this by clearing any pending decrementer exceptions when L1 makes # the H_ENTER_NESTED hcall since it won't do this if it's decrementer # has gone negative, and anyway it's decrementer has been communicated # to L0 in the hdec_expires field and L0 will return control to L1 when # this goes negative by delivering an H_DECREMENTER exception. # # Fixes: 95a6432ce903 ("KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests") # Cc: stable@vger.kernel.org # v4.20+ # Signed-off-by: Suraj Jitindar Singh # Signed-off-by: Michael Ellerman # < /opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-gcc --version # < /opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-ld --version # < git log --format=%s --max-count=1 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479 # < make -s -j 24 ARCH=arm64 O=/kisskb/build/powerpc-next_arm64-defconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux- defconfig # make -s -j 24 ARCH=arm64 O=/kisskb/build/powerpc-next_arm64-defconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux- arch/arm64/Makefile:27: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum arch/arm64/Makefile:40: LSE atomics not supported by binutils /kisskb/src/net/ipv4/fib_semantics.c: In function 'fib_check_nh_v4_gw': /kisskb/src/net/ipv4/fib_semantics.c:1027:12: warning: 'err' may be used uninitialized in this function [-Wmaybe-uninitialized] if (!tbl || err) { ^ /kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c: In function 'sh_mobile_i2c_isr': /kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c:399:26: warning: 'data' may be used uninitialized in this function [-Wmaybe-uninitialized] pd->msg->buf[real_pos] = data; ^ /kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c:372:16: note: 'data' was declared here unsigned char data; ^ In file included from /kisskb/src/include/linux/rwsem.h:16:0, from /kisskb/src/include/linux/notifier.h:15, from /kisskb/src/include/linux/clk.h:17, from /kisskb/src/drivers/tty/serial/sh-sci.c:24: /kisskb/src/drivers/tty/serial/sh-sci.c: In function 'sci_dma_rx_submit': /kisskb/src/include/linux/spinlock.h:288:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized] _raw_spin_unlock_irqrestore(lock, flags); \ ^ /kisskb/src/drivers/tty/serial/sh-sci.c:1353:16: note: 'flags' was declared here unsigned long flags; ^ Completed OK # rm -rf /kisskb/build/powerpc-next_arm64-defconfig_arm64-gcc5.4 # Build took: 0:05:33.725111