Merge tag 'pull-tcg-20230915-2' of https://gitlab.com/rth7680/qemu into staging

*: Delete checks for old host definitions
tcg/loongarch64: Generate LSX instructions
fpu: Add conversions between bfloat16 and [u]int8
fpu: Handle m68k extended precision denormals properly
accel/tcg: Improve cputlb i/o organization
accel/tcg: Simplify tlb_plugin_lookup
accel/tcg: Remove false-negative halted assertion
tcg: Add gvec compare with immediate and scalar operand
tcg/aarch64: Emit BTI insns at jump landing pads

[Resolved conflict between CPUINFO_PMULL and CPUINFO_BTI.
--Stefan]

* tag 'pull-tcg-20230915-2' of https://gitlab.com/rth7680/qemu: (39 commits)
  tcg: Map code_gen_buffer with PROT_BTI
  tcg/aarch64: Emit BTI insns at jump landing pads
  util/cpuinfo-aarch64: Add CPUINFO_BTI
  tcg: Add tcg_out_tb_start backend hook
  fpu: Handle m68k extended precision denormals properly
  fpu: Add conversions between bfloat16 and [u]int8
  accel/tcg: Introduce do_st16_mmio_leN
  accel/tcg: Introduce do_ld16_mmio_beN
  accel/tcg: Merge io_writex into do_st_mmio_leN
  accel/tcg: Merge io_readx into do_ld_mmio_beN
  accel/tcg: Replace direct use of io_readx/io_writex in do_{ld,st}_1
  accel/tcg: Merge cpu_transaction_failed into io_failed
  plugin: Simplify struct qemu_plugin_hwaddr
  accel/tcg: Use CPUTLBEntryFull.phys_addr in io_failed
  accel/tcg: Split out io_prepare and io_failed
  accel/tcg: Simplify tlb_plugin_lookup
  target/arm: Use tcg_gen_gvec_cmpi for compare vs 0
  tcg: Add gvec compare with immediate and scalar operand
  tcg/loongarch64: Implement 128-bit load & store
  tcg/loongarch64: Lower rotli_vec to vrotri
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

2 files changed, 10 insertions, 12 deletions

diff --git a/util/cpuinfo-aarch64.c b/util/cpuinfo-aarch64.c
index e0e1fe6..4c8a005 100644
--- a/util/cpuinfo-aarch64.c
+++ b/util/cpuinfo-aarch64.c
@@ -13,6 +13,9 @@
 #  include <asm/hwcap.h>
 #  include "elf.h"
 # endif
+# ifndef HWCAP2_BTI
+#  define HWCAP2_BTI 0  /* added in glibc 2.32 */
+# endif
 #endif
 #ifdef CONFIG_DARWIN
 # include <sys/sysctl.h>
@@ -58,12 +61,16 @@ unsigned __attribute__((constructor)) cpuinfo_init(void)
     info |= (hwcap & HWCAP_USCAT ? CPUINFO_LSE2 : 0);
     info |= (hwcap & HWCAP_AES ? CPUINFO_AES : 0);
     info |= (hwcap & HWCAP_PMULL ? CPUINFO_PMULL : 0);
+
+    unsigned long hwcap2 = qemu_getauxval(AT_HWCAP2);
+    info |= (hwcap2 & HWCAP2_BTI ? CPUINFO_BTI : 0);
 #endif
 #ifdef CONFIG_DARWIN
     info |= sysctl_for_bool("hw.optional.arm.FEAT_LSE") * CPUINFO_LSE;
     info |= sysctl_for_bool("hw.optional.arm.FEAT_LSE2") * CPUINFO_LSE2;
     info |= sysctl_for_bool("hw.optional.arm.FEAT_AES") * CPUINFO_AES;
     info |= sysctl_for_bool("hw.optional.arm.FEAT_PMULL") * CPUINFO_PMULL;
+    info |= sysctl_for_bool("hw.optional.arm.FEAT_BTI") * CPUINFO_BTI;
 #endif
 
     cpuinfo = info;
diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index 4d583da..e86fd64 100644
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -585,7 +585,7 @@ char *qemu_get_pid_name(pid_t pid)
 
 void *qemu_alloc_stack(size_t *sz)
 {
-    void *ptr, *guardpage;
+    void *ptr;
     int flags;
 #ifdef CONFIG_DEBUG_STACK_USAGE
     void *ptr2;
@@ -618,17 +618,8 @@ void *qemu_alloc_stack(size_t *sz)
         abort();
     }
 
-#if defined(HOST_IA64)
-    /* separate register stack */
-    guardpage = ptr + (((*sz - pagesz) / 2) & ~pagesz);
-#elif defined(HOST_HPPA)
-    /* stack grows up */
-    guardpage = ptr + *sz - pagesz;
-#else
-    /* stack grows down */
-    guardpage = ptr;
-#endif
-    if (mprotect(guardpage, pagesz, PROT_NONE) != 0) {
+    /* Stack grows down -- guard page at the bottom. */
+    if (mprotect(ptr, pagesz, PROT_NONE) != 0) {
         perror("failed to set up stack guard page");
         abort();
     }