Hi

Am 04.01.24 um 17:51 schrieb Ard Biesheuvel:

On Thu, 4 Jan 2024 at 10:54, Thomas Zimmermann [off-list ref] wrote:

quoted

Remove the include statement for <asm/bootparam.h> from several files
that don't require it. Limits the exposure of the boot parameters
within the Linux kernel code.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Ard Biesheuvel <ardb@kernel.org>

---

v3:
         * revert of e820/types.h required
v2:
         * clean up misc.h and e820/types.h
         * include bootparam.h in several source files
---
  arch/x86/boot/compressed/acpi.c       | 2 ++
  arch/x86/boot/compressed/cmdline.c    | 2 ++
  arch/x86/boot/compressed/efi.c        | 2 ++
  arch/x86/boot/compressed/misc.h       | 3 ++-
  arch/x86/boot/compressed/pgtable_64.c | 1 +
  arch/x86/boot/compressed/sev.c        | 1 +
  arch/x86/include/asm/kexec.h          | 1 -
  arch/x86/include/asm/mem_encrypt.h    | 2 +-
  arch/x86/include/asm/sev.h            | 3 ++-
  arch/x86/include/asm/x86_init.h       | 2 --
  arch/x86/kernel/crash.c               | 1 +
  arch/x86/kernel/sev-shared.c          | 2 ++
  arch/x86/platform/pvh/enlighten.c     | 1 +
  arch/x86/xen/enlighten_pvh.c          | 1 +
  arch/x86/xen/vga.c                    | 1 -
  15 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c
index 18d15d1ce87d..f196b1d1ddf8 100644
--- a/arch/x86/boot/compressed/acpi.c
+++ b/arch/x86/boot/compressed/acpi.c

@@ -5,6 +5,8 @@
  #include "../string.h"
  #include "efi.h"

+#include <asm/bootparam.h>
+
  #include <linux/numa.h>

  /*

diff --git a/arch/x86/boot/compressed/cmdline.c b/arch/x86/boot/compressed/cmdline.c
index c1bb180973ea..e162d7f59cc5 100644
--- a/arch/x86/boot/compressed/cmdline.c
+++ b/arch/x86/boot/compressed/cmdline.c

@@ -1,6 +1,8 @@
  // SPDX-License-Identifier: GPL-2.0
  #include "misc.h"

+#include <asm/bootparam.h>
+
  static unsigned long fs;
  static inline void set_fs(unsigned long seg)
  {

diff --git a/arch/x86/boot/compressed/efi.c b/arch/x86/boot/compressed/efi.c
index 6edd034b0b30..f2e50f9758e6 100644
--- a/arch/x86/boot/compressed/efi.c
+++ b/arch/x86/boot/compressed/efi.c

@@ -7,6 +7,8 @@

  #include "misc.h"

+#include <asm/bootparam.h>
+
  /**
   * efi_get_type - Given a pointer to boot_params, determine the type of EFI environment.
   *

diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index c0d502bd8716..01c89c410efd 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h

@@ -33,7 +33,6 @@
  #include <linux/elf.h>
  #include <asm/page.h>
  #include <asm/boot.h>
-#include <asm/bootparam.h>
  #include <asm/desc_defs.h>

  #include "tdx.h"

@@ -53,6 +52,8 @@
  #define memptr unsigned
  #endif

+struct boot_param;
+

Typo?

Indeed

Interestingly, it still builds fine for me without any warnings.

quoted

  /* boot/compressed/vmlinux start and end markers */
  extern char _head[], _end[];

diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c
index 51f957b24ba7..c882e1f67af0 100644
--- a/arch/x86/boot/compressed/pgtable_64.c
+++ b/arch/x86/boot/compressed/pgtable_64.c

@@ -1,5 +1,6 @@
  // SPDX-License-Identifier: GPL-2.0
  #include "misc.h"
+#include <asm/bootparam.h>
  #include <asm/e820/types.h>
  #include <asm/processor.h>
  #include "pgtable.h"

diff --git a/arch/x86/boot/compressed/sev.c b/arch/x86/boot/compressed/sev.c
index 454acd7a2daf..13beae767e48 100644
--- a/arch/x86/boot/compressed/sev.c
+++ b/arch/x86/boot/compressed/sev.c

@@ -12,6 +12,7 @@
   */
  #include "misc.h"

+#include <asm/bootparam.h>
  #include <asm/pgtable_types.h>
  #include <asm/sev.h>
  #include <asm/trapnr.h>

diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
index c9f6a6c5de3c..91ca9a9ee3a2 100644
--- a/arch/x86/include/asm/kexec.h
+++ b/arch/x86/include/asm/kexec.h

@@ -25,7 +25,6 @@

  #include <asm/page.h>
  #include <asm/ptrace.h>
-#include <asm/bootparam.h>

  struct kimage;

diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h
index 359ada486fa9..c1a8a3408c18 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h

@@ -15,7 +15,7 @@
  #include <linux/init.h>
  #include <linux/cc_platform.h>

-#include <asm/bootparam.h>
+struct boot_params;

Unfortunately, the SEV/SNP code is a bit of a kludge given that it
declares routines in headers under arch/x86/include/asm, and defines
them in two different places (the decompressor and the kernel proper).

So while I feel that we should avoid relying on incomplete struct
definitions, this one (and the one below) seems fine to me for now.
If/when someone gets around to cleaning up the SEV/SNP header files,
to split the init code from the more widely used mm types etc, we can
revisit this.

Thanks

quoted

  #ifdef CONFIG_X86_MEM_ENCRYPT
  void __init mem_encrypt_init(void);

diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h
index 5b4a1ce3d368..8dad8b1613bf 100644
--- a/arch/x86/include/asm/sev.h
+++ b/arch/x86/include/asm/sev.h

@@ -13,7 +13,6 @@

  #include <asm/insn.h>
  #include <asm/sev-common.h>
-#include <asm/bootparam.h>
  #include <asm/coco.h>

  #define GHCB_PROTOCOL_MIN      1ULL

@@ -22,6 +21,8 @@

  #define        VMGEXIT()                       { asm volatile("rep; vmmcall\n\r"); }

+struct boot_params;
+
  enum es_result {
         ES_OK,                  /* All good */
         ES_UNSUPPORTED,         /* Requested operation not supported */

diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index c878616a18b8..f062715578a0 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h

@@ -2,8 +2,6 @@
  #ifndef _ASM_X86_PLATFORM_H
  #define _ASM_X86_PLATFORM_H

-#include <asm/bootparam.h>
-
  struct ghcb;
  struct mpc_bus;
  struct mpc_cpu;

diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index c92d88680dbf..564cff7ed33a 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c

@@ -26,6 +26,7 @@
  #include <linux/vmalloc.h>
  #include <linux/memblock.h>

+#include <asm/bootparam.h>
  #include <asm/processor.h>
  #include <asm/hardirq.h>
  #include <asm/nmi.h>

diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c
index ccb0915e84e1..4962ec42dc68 100644
--- a/arch/x86/kernel/sev-shared.c
+++ b/arch/x86/kernel/sev-shared.c

@@ -9,6 +9,8 @@
   * and is included directly into both code-bases.
   */

+#include <asm/setup_data.h>
+
  #ifndef __BOOT_COMPRESSED
  #define error(v)       pr_err(v)
  #define has_cpuflag(f) boot_cpu_has(f)

diff --git a/arch/x86/platform/pvh/enlighten.c b/arch/x86/platform/pvh/enlighten.c
index 00a92cb2c814..944e0290f2c0 100644
--- a/arch/x86/platform/pvh/enlighten.c
+++ b/arch/x86/platform/pvh/enlighten.c

@@ -3,6 +3,7 @@

  #include <xen/hvc-console.h>

+#include <asm/bootparam.h>
  #include <asm/io_apic.h>
  #include <asm/hypervisor.h>
  #include <asm/e820/api.h>

diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c
index ada3868c02c2..9e9db601bd52 100644
--- a/arch/x86/xen/enlighten_pvh.c
+++ b/arch/x86/xen/enlighten_pvh.c

@@ -4,6 +4,7 @@

  #include <xen/hvc-console.h>

+#include <asm/bootparam.h>
  #include <asm/io_apic.h>
  #include <asm/hypervisor.h>
  #include <asm/e820/api.h>

diff --git a/arch/x86/xen/vga.c b/arch/x86/xen/vga.c
index d97adab8420f..f7547807b0bd 100644
--- a/arch/x86/xen/vga.c
+++ b/arch/x86/xen/vga.c

@@ -2,7 +2,6 @@
  #include <linux/screen_info.h>
  #include <linux/init.h>

-#include <asm/bootparam.h>
  #include <asm/setup.h>

  #include <xen/interface/xen.h>
--

2.43.0

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)