Date:   Wed, 8 Feb 2023 16:12:51 -0500
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     qemu-devel@nongnu.org, "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org,
        Dov Murik <dovmurik@linux.ibm.com>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Gerd Hoffmann <kraxel@redhat.com>,
        Daniel P =?utf-8?B?LiBCZXJyYW5nw6k=?= <berrange@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Richard Henderson <richard.henderson@linaro.org>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= <philmd@linaro.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Borislav Petkov <bp@alien8.de>,
        Eric Biggers <ebiggers@kernel.org>,
        Marcel Apfelbaum <marcel.apfelbaum@gmail.com>,
        Eduardo Habkost <eduardo@habkost.net>
Subject: [PATCH RFC 6/7] Revert "x86: return modified setup_data only if read
 as memory, not as file"
Message-ID: <20230208211212.41951-7-mst@redhat.com>
References: <20230208211212.41951-1-mst@redhat.com>
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In-Reply-To: <20230208211212.41951-1-mst@redhat.com>
Precedence: bulk

This reverts commit e935b735085dfa61d8e6d276b6f9e7687796a3c7.

Fixes: e935b73508 ("x86: return modified setup_data only if read as memory, not as file")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 include/hw/nvram/fw_cfg.h | 22 -------------------
 hw/i386/x86.c             | 46 +++++++++------------------------------
 hw/nvram/fw_cfg.c         | 12 +++++-----
 3 files changed, 16 insertions(+), 64 deletions(-)

diff --git a/include/hw/nvram/fw_cfg.h b/include/hw/nvram/fw_cfg.h
index 2e503904dc..c1f81a5f13 100644
--- a/include/hw/nvram/fw_cfg.h
+++ b/include/hw/nvram/fw_cfg.h
@@ -117,28 +117,6 @@ struct FWCfgMemState {
  */
 void fw_cfg_add_bytes(FWCfgState *s, uint16_t key, void *data, size_t len);
 
-/**
- * fw_cfg_add_bytes_callback:
- * @s: fw_cfg device being modified
- * @key: selector key value for new fw_cfg item
- * @select_cb: callback function when selecting
- * @write_cb: callback function after a write
- * @callback_opaque: argument to be passed into callback function
- * @data: pointer to start of item data
- * @len: size of item data
- * @read_only: is file read only
- *
- * Add a new fw_cfg item, available by selecting the given key, as a raw
- * "blob" of the given size. The data referenced by the starting pointer
- * is only linked, NOT copied, into the data structure of the fw_cfg device.
- */
-void fw_cfg_add_bytes_callback(FWCfgState *s, uint16_t key,
-                               FWCfgCallback select_cb,
-                               FWCfgWriteCallback write_cb,
-                               void *callback_opaque,
-                               void *data, size_t len,
-                               bool read_only);
-
 /**
  * fw_cfg_add_string:
  * @s: fw_cfg device being modified
diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index 76b12108b4..4831193c86 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -37,7 +37,6 @@
 #include "sysemu/whpx.h"
 #include "sysemu/numa.h"
 #include "sysemu/replay.h"
-#include "sysemu/reset.h"
 #include "sysemu/sysemu.h"
 #include "sysemu/cpu-timers.h"
 #include "sysemu/xen.h"
@@ -769,24 +768,6 @@ static bool load_elfboot(const char *kernel_filename,
     return true;
 }
 
-typedef struct SetupDataFixup {
-    void *pos;
-    hwaddr orig_val, new_val;
-    uint32_t addr;
-} SetupDataFixup;
-
-static void fixup_setup_data(void *opaque)
-{
-    SetupDataFixup *fixup = opaque;
-    stq_p(fixup->pos, fixup->new_val);
-}
-
-static void reset_setup_data(void *opaque)
-{
-    SetupDataFixup *fixup = opaque;
-    stq_p(fixup->pos, fixup->orig_val);
-}
-
 void x86_load_linux(X86MachineState *x86ms,
                     FWCfgState *fw_cfg,
                     int acpi_data_size,
@@ -1111,11 +1092,8 @@ void x86_load_linux(X86MachineState *x86ms,
         qemu_guest_getrandom_nofail(setup_data->data, RNG_SEED_LENGTH);
     }
 
-    fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ADDR, prot_addr);
-    fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_SIZE, kernel_size);
-    fw_cfg_add_bytes(fw_cfg, FW_CFG_KERNEL_DATA, kernel, kernel_size);
-    sev_load_ctx.kernel_data = (char *)kernel;
-    sev_load_ctx.kernel_size = kernel_size;
+    /* Offset 0x250 is a pointer to the first setup_data link. */
+    stq_p(header + 0x250, first_setup_data);
 
     /*
      * If we're starting an encrypted VM, it will be OVMF based, which uses the
@@ -1125,20 +1103,16 @@ void x86_load_linux(X86MachineState *x86ms,
      * file the user passed in.
      */
     if (!sev_enabled()) {
-        SetupDataFixup *fixup = g_malloc(sizeof(*fixup));
-
         memcpy(setup, header, MIN(sizeof(header), setup_size));
-        /* Offset 0x250 is a pointer to the first setup_data link. */
-        fixup->pos = setup + 0x250;
-        fixup->orig_val = ldq_p(fixup->pos);
-        fixup->new_val = first_setup_data;
-        fixup->addr = cpu_to_le32(real_addr);
-        fw_cfg_add_bytes_callback(fw_cfg, FW_CFG_SETUP_ADDR, fixup_setup_data, NULL,
-                                  fixup, &fixup->addr, sizeof(fixup->addr), true);
-        qemu_register_reset(reset_setup_data, fixup);
-    } else {
-        fw_cfg_add_i32(fw_cfg, FW_CFG_SETUP_ADDR, real_addr);
     }
+
+    fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ADDR, prot_addr);
+    fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_SIZE, kernel_size);
+    fw_cfg_add_bytes(fw_cfg, FW_CFG_KERNEL_DATA, kernel, kernel_size);
+    sev_load_ctx.kernel_data = (char *)kernel;
+    sev_load_ctx.kernel_size = kernel_size;
+
+    fw_cfg_add_i32(fw_cfg, FW_CFG_SETUP_ADDR, real_addr);
     fw_cfg_add_i32(fw_cfg, FW_CFG_SETUP_SIZE, setup_size);
     fw_cfg_add_bytes(fw_cfg, FW_CFG_SETUP_DATA, setup, setup_size);
     sev_load_ctx.setup_data = (char *)setup;
diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index a00881bc64..29a5bef1d5 100644
--- a/hw/nvram/fw_cfg.c
+++ b/hw/nvram/fw_cfg.c
@@ -693,12 +693,12 @@ static const VMStateDescription vmstate_fw_cfg = {
     }
 };
 
-void fw_cfg_add_bytes_callback(FWCfgState *s, uint16_t key,
-                               FWCfgCallback select_cb,
-                               FWCfgWriteCallback write_cb,
-                               void *callback_opaque,
-                               void *data, size_t len,
-                               bool read_only)
+static void fw_cfg_add_bytes_callback(FWCfgState *s, uint16_t key,
+                                      FWCfgCallback select_cb,
+                                      FWCfgWriteCallback write_cb,
+                                      void *callback_opaque,
+                                      void *data, size_t len,
+                                      bool read_only)
 {
     int arch = !!(key & FW_CFG_ARCH_LOCAL);
 
-- 
MST