On Thu, Nov 4, 2021 at 4:40 AM Borislav Petkov bp@alien8.de wrote:
- 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.
Thanks Boris!
You can add:
Tested-by: Anjaneya Chagam anjaneya.chagam@intel.com Reviewed-by: Dan Williams dan.j.williams@intel.com
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.