Revert "x86/boot: Pull up cmdline preparation and early param parsing"

commit fbe6183998546f8896ee0b620ece86deff5a2fd1 upstream.

This reverts commit 8d48bf8206f77aa8687f0e241e901e5197e52423.

It turned out to be a bad idea as it broke supplying mem= cmdline
parameters due to parse_memopt() requiring preparatory work like setting
up the e820 table in e820__memory_setup() in order to be able to exclude
the range specified by mem=.

Pulling that up would've broken Xen PV again, see threads at

  https://lkml.kernel.org/r/20210920120421.29276-1-jgross@suse.com

due to xen_memory_setup() needing the first reservations in
early_reserve_memory() - kernel and initrd - to have happened already.

This could be fixed again by having Xen do those reservations itself...

Long story short, revert this and do a simpler fix in a later patch.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211213112757.2612-3-bp@alien8.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index d71267081153f55f05fd97450fc3235dcc196152..40ed44ead0631288b16f98e233464994eb09e062 100644 (file)
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -742,28 +742,6 @@ dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
        return 0;
 }
 
-static char *prepare_command_line(void)
-{
-#ifdef CONFIG_CMDLINE_BOOL
-#ifdef CONFIG_CMDLINE_OVERRIDE
-       strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
-#else
-       if (builtin_cmdline[0]) {
-               /* append boot loader cmdline to builtin */
-               strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
-               strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
-               strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
-       }
-#endif
-#endif
-
-       strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
-
-       parse_early_param();
-
-       return command_line;
-}
-
 /*
  * Determine if we were loaded by an EFI loader.  If so, then we have also been
  * passed the efi memmap, systab, etc., so we should use these data structures
@@ -852,23 +830,6 @@ void __init setup_arch(char **cmdline_p)
 
        x86_init.oem.arch_setup();
 
-       /*
-        * x86_configure_nx() is called before parse_early_param() (called by
-        * prepare_command_line()) to detect whether hardware doesn't support
-        * NX (so that the early EHCI debug console setup can safely call
-        * set_fixmap()). It may then be called again from within noexec_setup()
-        * during parsing early parameters to honor the respective command line
-        * option.
-        */
-       x86_configure_nx();
-
-       /*
-        * This parses early params and it needs to run before
-        * early_reserve_memory() because latter relies on such settings
-        * supplied as early params.
-        */
-       *cmdline_p = prepare_command_line();
-
        /*
         * Do some memory reservations *before* memory is added to memblock, so
         * memblock allocations won't overwrite it.
@@ -902,6 +863,33 @@ void __init setup_arch(char **cmdline_p)
        bss_resource.start = __pa_symbol(__bss_start);
        bss_resource.end = __pa_symbol(__bss_stop)-1;
 
+#ifdef CONFIG_CMDLINE_BOOL
+#ifdef CONFIG_CMDLINE_OVERRIDE
+       strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
+#else
+       if (builtin_cmdline[0]) {
+               /* append boot loader cmdline to builtin */
+               strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
+               strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
+               strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
+       }
+#endif
+#endif
+
+       strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
+       *cmdline_p = command_line;
+
+       /*
+        * x86_configure_nx() is called before parse_early_param() to detect
+        * whether hardware doesn't support NX (so that the early EHCI debug
+        * console setup can safely call set_fixmap()). It may then be called
+        * again from within noexec_setup() during parsing early parameters
+        * to honor the respective command line option.
+        */
+       x86_configure_nx();
+
+       parse_early_param();
+
 #ifdef CONFIG_MEMORY_HOTPLUG
        /*
         * Memory used by the kernel cannot be hot-removed because Linux