[xen stable-4.17] x86: fix build with old gcc after CPU policy changes

[patchbot@xxxxxxx]

commit 7d8897984927a51495e9a1b827aa4bce1d779b87
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Mon Aug 21 15:53:17 2023 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Aug 21 15:53:17 2023 +0200

    x86: fix build with old gcc after CPU policy changes
    
    Old gcc won't cope with initializers involving unnamed struct/union
    fields.
    
    Fixes: 441b1b2a50ea ("x86/emul: Switch x86_emulate_ctxt to cpu_policy")
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Acked-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    master commit: 768846690d64bc730c1a1123e8de3af731bb2eb3
    master date: 2023-04-19 11:02:47 +0200
---
 tools/fuzz/x86_instruction_emulator/fuzz-emul.c | 4 +++-
 xen/arch/x86/pv/emul-priv-op.c                  | 4 +++-
 xen/arch/x86/pv/ro-page-fault.c                 | 4 +++-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/tools/fuzz/x86_instruction_emulator/fuzz-emul.c 
b/tools/fuzz/x86_instruction_emulator/fuzz-emul.c
index 4885a68210..eeeb6931f4 100644
--- a/tools/fuzz/x86_instruction_emulator/fuzz-emul.c
+++ b/tools/fuzz/x86_instruction_emulator/fuzz-emul.c
@@ -893,12 +893,14 @@ int LLVMFuzzerTestOneInput(const uint8_t *data_p, size_t 
size)
     struct x86_emulate_ctxt ctxt = {
         .data = &state,
         .regs = &input.regs,
-        .cpu_policy = &cp,
         .addr_size = 8 * sizeof(void *),
         .sp_size = 8 * sizeof(void *),
     };
     int rc;
 
+    /* Not part of the initializer, for old gcc to cope. */
+    ctxt.cpu_policy = &cp;
+
     /* Reset all global state variables */
     memset(&input, 0, sizeof(input));
 
diff --git a/xen/arch/x86/pv/emul-priv-op.c b/xen/arch/x86/pv/emul-priv-op.c
index 04416f1979..2c94beb10e 100644
--- a/xen/arch/x86/pv/emul-priv-op.c
+++ b/xen/arch/x86/pv/emul-priv-op.c
@@ -1327,12 +1327,14 @@ int pv_emulate_privileged_op(struct cpu_user_regs *regs)
     struct domain *currd = curr->domain;
     struct priv_op_ctxt ctxt = {
         .ctxt.regs = regs,
-        .ctxt.cpu_policy = currd->arch.cpu_policy,
         .ctxt.lma = !is_pv_32bit_domain(currd),
     };
     int rc;
     unsigned int eflags, ar;
 
+    /* Not part of the initializer, for old gcc to cope. */
+    ctxt.ctxt.cpu_policy = currd->arch.cpu_policy;
+
     if ( !pv_emul_read_descriptor(regs->cs, curr, &ctxt.cs.base,
                                   &ctxt.cs.limit, &ar, 1) ||
          !(ar & _SEGMENT_S) ||
diff --git a/xen/arch/x86/pv/ro-page-fault.c b/xen/arch/x86/pv/ro-page-fault.c
index 0d02c7d2ab..f23ad5d184 100644
--- a/xen/arch/x86/pv/ro-page-fault.c
+++ b/xen/arch/x86/pv/ro-page-fault.c
@@ -356,7 +356,6 @@ int pv_ro_page_fault(unsigned long addr, struct 
cpu_user_regs *regs)
     unsigned int addr_size = is_pv_32bit_domain(currd) ? 32 : BITS_PER_LONG;
     struct x86_emulate_ctxt ctxt = {
         .regs      = regs,
-        .cpu_policy = currd->arch.cpu_policy,
         .addr_size = addr_size,
         .sp_size   = addr_size,
         .lma       = addr_size > 32,
@@ -364,6 +363,9 @@ int pv_ro_page_fault(unsigned long addr, struct 
cpu_user_regs *regs)
     int rc;
     bool mmio_ro;
 
+    /* Not part of the initializer, for old gcc to cope. */
+    ctxt.cpu_policy = currd->arch.cpu_policy;
+
     /* Attempt to read the PTE that maps the VA being accessed. */
     pte = guest_get_eff_kern_l1e(addr);
 
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.17