[PULL 0/3] misc tcg-related patches

[PULL 0/3] misc tcg-related patches

[Richard Henderson]

The following changes since commit 7adfbea8fd1efce36019a0c2f198ca73be9d3f18:

  Merge remote-tracking branch 'remotes/ehabkost/tags/x86-next-for-5.1-pull-request' into staging (2020-07-24 10:52:20 +0100)

are available in the Git repository at:

  https://github.com/rth7680/qemu.git tags/pull-tcg-20200725

for you to fetch changes up to 3cb3a7720b01830abd5fbb81819dbb9271bf7821:

  target/i386: Save cc_op before loop insns (2020-07-24 14:29:35 -0700)

----------------------------------------------------------------
Fix some cputlb commentary
Fix an hppa temporary leak
Fix an i386 translation issue with loop insns

----------------------------------------------------------------
Alex Bennée (1):
      tcg: update comments for save_iotlb_data in cputlb

Richard Henderson (2):
      target/hppa: Free some temps in do_sub
      target/i386: Save cc_op before loop insns

 accel/tcg/cputlb.c      | 11 +++++------
 target/hppa/translate.c |  2 ++
 target/i386/translate.c |  1 +
 3 files changed, 8 insertions(+), 6 deletions(-)

[PULL 1/3] tcg: update comments for save_iotlb_data in cputlb

[Richard Henderson]

From: Alex Bennée <alex.bennee@linaro.org>

I missed Emilio's review comments:

  Message-ID: <20200718205107.GA994221@sff>

and the patch got merged. Correcting the comments now.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200720122358.26881-1-alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 accel/tcg/cputlb.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c
index d370aedb47..5698292749 100644
--- a/accel/tcg/cputlb.c
+++ b/accel/tcg/cputlb.c
@@ -1075,10 +1075,8 @@ static uint64_t io_readx(CPUArchState *env, CPUIOTLBEntry *iotlbentry,
 
 /*
  * Save a potentially trashed IOTLB entry for later lookup by plugin.
- *
- * We also need to track the thread storage address because the RCU
- * cleanup that runs when we leave the critical region (the current
- * execution) is actually in a different thread.
+ * This is read by tlb_plugin_lookup if the iotlb entry doesn't match
+ * because of the side effect of io_writex changing memory layout.
  */
 static void save_iotlb_data(CPUState *cs, hwaddr addr,
                             MemoryRegionSection *section, hwaddr mr_offset)
@@ -1408,8 +1406,9 @@ void *tlb_vaddr_to_host(CPUArchState *env, abi_ptr addr,
  * This almost never fails as the memory access being instrumented
  * should have just filled the TLB. The one corner case is io_writex
  * which can cause TLB flushes and potential resizing of the TLBs
- * loosing the information we need. In those cases we need to recover
- * data from a copy of the io_tlb entry.
+ * losing the information we need. In those cases we need to recover
+ * data from a copy of the iotlbentry. As long as this always occurs
+ * from the same thread (which a mem callback will be) this is safe.
  */
 
 bool tlb_plugin_lookup(CPUState *cpu, target_ulong addr, int mmu_idx,
-- 
2.25.1

[PULL 2/3] target/hppa: Free some temps in do_sub

[Richard Henderson]

Two temps allocated but not freed.  Do enough subtractions
within a single TB and one can run out of temps entirely.

Fixes: b2167459ae ("target-hppa: Implement basic arithmetic")
Buglink: https://bugs.launchpad.net/qemu/+bug/1880287
Tested-by: Sven Schnelle <svens@stackframe.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200720174039.517902-1-richard.henderson@linaro.org>
---
 target/hppa/translate.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/target/hppa/translate.c b/target/hppa/translate.c
index 52d7bea1ea..4bd22d4820 100644
--- a/target/hppa/translate.c
+++ b/target/hppa/translate.c
@@ -1294,6 +1294,8 @@ static void do_sub(DisasContext *ctx, unsigned rt, TCGv_reg in1,
     save_or_nullify(ctx, cpu_psw_cb_msb, cb_msb);
     save_gpr(ctx, rt, dest);
     tcg_temp_free(dest);
+    tcg_temp_free(cb);
+    tcg_temp_free(cb_msb);
 
     /* Install the new nullification.  */
     cond_free(&ctx->null_cond);
-- 
2.25.1

[PULL 3/3] target/i386: Save cc_op before loop insns

[Richard Henderson]

We forgot to update cc_op before these branch insns,
which lead to losing track of the current eflags.

Buglink: https://bugs.launchpad.net/qemu/+bug/1888165
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200720154028.477457-1-richard.henderson@linaro.org>
---
 target/i386/translate.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/target/i386/translate.c b/target/i386/translate.c
index a1d31f09c1..caea6f5fb1 100644
--- a/target/i386/translate.c
+++ b/target/i386/translate.c
@@ -7148,6 +7148,7 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
             l1 = gen_new_label();
             l2 = gen_new_label();
             l3 = gen_new_label();
+            gen_update_cc_op(s);
             b &= 3;
             switch(b) {
             case 0: /* loopnz */
-- 
2.25.1

Re: [PULL 0/3] misc tcg-related patches

[Peter Maydell]

On Sat, 25 Jul 2020 at 17:05, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> The following changes since commit 7adfbea8fd1efce36019a0c2f198ca73be9d3f18:
>
>   Merge remote-tracking branch 'remotes/ehabkost/tags/x86-next-for-5.1-pull-request' into staging (2020-07-24 10:52:20 +0100)
>
> are available in the Git repository at:
>
>   https://github.com/rth7680/qemu.git tags/pull-tcg-20200725
>
> for you to fetch changes up to 3cb3a7720b01830abd5fbb81819dbb9271bf7821:
>
>   target/i386: Save cc_op before loop insns (2020-07-24 14:29:35 -0700)
>
> ----------------------------------------------------------------
> Fix some cputlb commentary
> Fix an hppa temporary leak
> Fix an i386 translation issue with loop insns
>
> ---------------------------------------------------------------


Applied, thanks.

Please update the changelog at https://wiki.qemu.org/ChangeLog/5.1
for any user-visible changes.

-- PMM