diff options
| author | Joerg Roedel <jroedel@suse.de> | 2021-12-02 16:32:25 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-01-27 11:04:35 +0100 |
| commit | 30bd6733ef960e02fcbac7f2bedb9df1830a5a7d (patch) | |
| tree | bc482d4844ab3163e05a9f157e23674e68a77e10 /arch/x86/kernel/reboot.c | |
| parent | 1b4422befeba0cb77149ca6a0907077f65f788d1 (diff) | |
x86/mm: Flush global TLB when switching to trampoline page-table
[ Upstream commit 71d5049b053876afbde6c3273250b76935494ab2 ]
Move the switching code into a function so that it can be re-used and
add a global TLB flush. This makes sure that usage of memory which is
not mapped in the trampoline page-table is reliably caught.
Also move the clearing of CR4.PCIDE before the CR3 switch because the
cr4_clear_bits() function will access data not mapped into the
trampoline page-table.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211202153226.22946-4-joro@8bytes.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/x86/kernel/reboot.c')
| -rw-r--r-- | arch/x86/kernel/reboot.c | 12 |
1 files changed, 2 insertions, 10 deletions
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 0a40df66a40d..fa700b46588e 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -113,17 +113,9 @@ void __noreturn machine_real_restart(unsigned int type) spin_unlock(&rtc_lock); /* - * Switch back to the initial page table. + * Switch to the trampoline page table. */ -#ifdef CONFIG_X86_32 - load_cr3(initial_page_table); -#else - write_cr3(real_mode_header->trampoline_pgd); - - /* Exiting long mode will fail if CR4.PCIDE is set. */ - if (boot_cpu_has(X86_FEATURE_PCID)) - cr4_clear_bits(X86_CR4_PCIDE); -#endif + load_trampoline_pgtable(); /* Jump to the identity-mapped low memory code */ #ifdef CONFIG_X86_32 |