Mailing List Archive

commit e44d986084760929e32bd4f5456677d370206d7f
Author: Trammell Hudson <hudson@trmm.net>
AuthorDate: Wed Aug 12 17:42:48 2020 +0000
Commit: Andrew Cooper <andrew.cooper3@citrix.com>
CommitDate: Thu Aug 13 12:42:24 2020 +0100

x86/setup: Ignore early boot parameters like no-real-mode

There are parameters in xen/arch/x86/boot/cmdline.c that
are only used early in the boot process, so handlers are
necessary to avoid an "Unknown command line option" in
dmesg.

This also updates ignore_param() to generate a temporary
variable name so that the macro can be used more than once
per file.

Signed-off-by: Trammell hudson <hudson@trmm.net>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
[Leave note to stop TEMP_NAME() finding more general use]
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
xen/arch/x86/setup.c | 9 +++++++++
xen/include/xen/param.h | 11 ++++++++---
2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index c9b6af826d..4b15e067fa 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -679,6 +679,15 @@ static void __init noreturn reinit_bsp_stack(void)
reset_stack_and_jump_nolp(init_done);
}

+/*
+ * x86 early command line parsing in xen/arch/x86/boot/cmdline.c
+ * has options that are only used during the very initial boot process,
+ * so they can be ignored now.
+ */
+ignore_param("no-real-mode");
+ignore_param("edd");
+ignore_param("edid");
+
/*
* Some scripts add "placeholder" to work around a grub error where it ate the
* first parameter.
diff --git a/xen/include/xen/param.h b/xen/include/xen/param.h
index c2fd075dd0..f4be944248 100644
--- a/xen/include/xen/param.h
+++ b/xen/include/xen/param.h
@@ -35,6 +35,11 @@ extern const struct kernel_param __setup_start[], __setup_end[];
__attribute__((__aligned__(1))) char
#define __kparam __param(__initsetup)

+/* Only for use with .init data, to avoid creating livepatch problems. */
+#define __TEMP_NAME(base, line) base ## _ ## line
+#define _TEMP_NAME(base, line) __TEMP_NAME(base, line)
+#define TEMP_NAME(base) _TEMP_NAME(base, __LINE__)
+
#define custom_param(_name, _var) \
__setup_str __setup_str_##_var[] = _name; \
__kparam __setup_##_var = \
@@ -71,9 +76,9 @@ extern const struct kernel_param __setup_start[], __setup_end[];
.len = sizeof(_var), \
.par.var = &_var }
#define ignore_param(_name) \
- __setup_str setup_str_ign[] = _name; \
- __kparam setup_ign = \
- { .name = setup_str_ign, \
+ __setup_str TEMP_NAME(__setup_str_ign)[] = _name; \
+ __kparam TEMP_NAME(__setup_ign) = \
+ { .name = TEMP_NAME(__setup_str_ign), \
.type = OPT_IGNORE }

#ifdef CONFIG_HYPFS
--
generated by git-patchbot for /home/xen/git/xen.git#staging