Messages in this thread Patch in this message | | | Date | Tue, 8 Jun 2021 22:01:50 +0200 | From | Borislav Petkov <> | Subject | Re: [GIT PULL] x86/urgent for v5.13-rc5 |
| |
On Tue, Jun 08, 2021 at 12:22:50PM -0700, Linus Torvalds wrote: > On Tue, Jun 8, 2021 at 11:33 AM Borislav Petkov <bp@alien8.de> wrote: > > > > Linus, maybe we should at least give it a try and see whether someone > > complains and revert, potentially...? > > I already merged the change that did that.
Oh yeah, I meant: let's leave it in and try it and only revert if there's trouble.
> It might be worth adding a comment about the verified Windows behavior > here, but I think otherwise we're all done.
How's that (comment re-flowed):
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 1e720626069a..b58cdc70f86b 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -1084,17 +1084,18 @@ void __init setup_arch(char **cmdline_p) #endif /* - * Find free memory for the real mode trampoline and place it - * there. - * If there is not enough free memory under 1M, on EFI-enabled - * systems there will be additional attempt to reclaim the memory - * for the real mode trampoline at efi_free_boot_services(). + * Find free memory for the real mode trampoline and place it there. If + * there is not enough free memory under 1M, on EFI-enabled systems + * there will be additional attempt to reclaim the memory for the real + * mode trampoline at efi_free_boot_services(). * - * Unconditionally reserve the entire first 1M of RAM because - * BIOSes are know to corrupt low memory and several - * hundred kilobytes are not worth complex detection what memory gets - * clobbered. Moreover, on machines with SandyBridge graphics or in - * setups that use crashkernel the entire 1M is reserved anyway. + * Unconditionally reserve the entire first 1M of RAM because BIOSes + * are known to corrupt low memory and several hundred kilobytes are not + * worth complex detection what memory gets clobbered. Windows does the + * same thing for very similar reasons. + * + * Moreover, on machines with SandyBridge graphics or in setups that use + * crashkernel the entire 1M is reserved anyway. */ reserve_real_mode(); Thx.
-- Regards/Gruss, Boris.
https://people.kernel.org/tglx/notes-about-netiquette
| |