+ Mike.
On Thu, Nov 04, 2021 at 05:38:54AM +0000, Williams, Dan J wrote:
> By inspection, this commit looks like the source of the problem because
> early_reserve_memory() now runs before parse_early_param().
Yah, I see it too:
early_reserve_memory
|-> efi_memblock_x86_reserve_range
|-> efi_fake_memmap_early
which does
if (!efi_soft_reserve_enabled())
return;
and that would have set EFI_MEM_NO_SOFT_RESERVE after having parsed
"nosoftreserve".
And parse_early_param() happens later.
Uuuf, that early memory reservation dance is not going to be over,
ever...
Well, I guess we can do something like this below. The intent being to
carve out the command line preparation into a separate function which
does the early param parsing too. So that it all goes together.
And then call that function before early_reserve_memory() so that the
params have been parsed by then.
Looking at the changed flow, I think we should be ok but I've said that
a bunch of times already regarding this memory reservation early and
something in our house of cards called early boot order always broke.
Damn.
---
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 40ed44ead063..05f69e7d84dc 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -742,6 +742,28 @@ 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
@@ -830,6 +852,23 @@ 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
+ * supplies 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.
@@ -863,33 +902,6 @@ 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
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
