# git rev-parse -q --verify 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479^{commit}
3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479
already have revision, skipping fetch
# git checkout -q -f -B kisskb 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479
# git clean -qxdf
# < git log -1
# commit 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479
# Author: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
# 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 <sjitindarsingh@gmail.com>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/hppa-linux/bin/hppa-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/hppa-linux/bin/hppa-linux-ld --version
# < git log --format=%s --max-count=1 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479
# < make -s -j 48 ARCH=parisc O=/kisskb/build/powerpc-next_parisc-defconfig_parisc CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/hppa-linux/bin/hppa-linux-  defconfig
# make -s -j 48 ARCH=parisc O=/kisskb/build/powerpc-next_parisc-defconfig_parisc CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/hppa-linux/bin/hppa-linux-  
In file included from /kisskb/src/arch/parisc/math-emu/fcnvxf.c:51:
/kisskb/src/arch/parisc/math-emu/fcnvxf.c: In function 'sgl_to_sgl_fcnvxf':
/kisskb/src/arch/parisc/math-emu/cnv_float.h:63:52: warning: '<<' in boolean context, did you mean '<' ? [-Wint-in-bool-context]
 #define Int_isinexact_to_sgl(int_value) (int_value << 33 - SGL_EXP_LENGTH)
                                         ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
/kisskb/src/arch/parisc/math-emu/fcnvxf.c:101:6: note: in expansion of macro 'Int_isinexact_to_sgl'
  if (Int_isinexact_to_sgl(src)) {
      ^~~~~~~~~~~~~~~~~~~~
/kisskb/src/arch/parisc/math-emu/cnv_float.h:67:21: warning: '<<' in boolean context, did you mean '<' ? [-Wint-in-bool-context]
      if ((int_value << 34 - SGL_EXP_LENGTH) || Slow(sgl_value)) \
          ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
/kisskb/src/arch/parisc/math-emu/fcnvxf.c:112:5: note: in expansion of macro 'Sgl_roundnearest_from_int'
     Sgl_roundnearest_from_int(src,result);
     ^~~~~~~~~~~~~~~~~~~~~~~~~
/kisskb/src/arch/parisc/math-emu/fcnvxf.c: In function 'dbl_to_sgl_fcnvxf':
/kisskb/src/arch/parisc/math-emu/cnv_float.h:71:27: warning: '<<' in boolean context, did you mean '<' ? [-Wint-in-bool-context]
     ((Dintp1(dint_valueA) << 33 - SGL_EXP_LENGTH) || Dintp2(dint_valueB))
      ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
/kisskb/src/arch/parisc/math-emu/fcnvxf.c:257:6: note: in expansion of macro 'Dint_isinexact_to_sgl'
  if (Dint_isinexact_to_sgl(srcp1,srcp2)) {
      ^~~~~~~~~~~~~~~~~~~~~
/kisskb/src/arch/parisc/math-emu/cnv_float.h:75:31: warning: '<<' in boolean context, did you mean '<' ? [-Wint-in-bool-context]
      if ((Dintp1(dint_valueA) << 34 - SGL_EXP_LENGTH) ||  \
          ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
/kisskb/src/arch/parisc/math-emu/fcnvxf.c:268:5: note: in expansion of macro 'Sgl_roundnearest_from_dint'
     Sgl_roundnearest_from_dint(srcp1,srcp2,result);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~
Completed OK
# rm -rf /kisskb/build/powerpc-next_parisc-defconfig_parisc
# Build took: 0:01:05.635843