On Mon, Aug 05, 2024 at 09:52:06PM -0700, Guenter Roeck wrote: > Hi Peter, > > On Thu, Aug 01, 2024 at 10:55:31AM -0000, tip-bot2 for Peter Zijlstra wrote: > > The following commit has been merged into the x86/urgent branch of tip: > > > > Commit-ID: 49947e7aedfea2573bada0c95b85f6c2363bef9f > > Gitweb: https://git.kernel.org/tip/49947e7aedfea2573bada0c95b85f6c2363bef9f > > Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > > AuthorDate: Thu, 01 Aug 2024 12:42:25 +02:00 > > Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > > CommitterDate: Thu, 01 Aug 2024 12:48:23 +02:00 > > > > x86/mm: Fix pti_clone_entry_text() for i386 > > > > While x86_64 has PMD aligned text sections, i386 does not have this > > luxery. Notably ALIGN_ENTRY_TEXT_END is empty and _etext has PAGE > > alignment. > > > > This means that text on i386 can be page granular at the tail end, > > which in turn means that the PTI text clones should consistently > > account for this. > > > > Make pti_clone_entry_text() consistent with pti_clone_kernel_text(). > > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> > > With this patch in the tree, some of my qemu tests (those with PAE enabled) > report several WARNING backtraces. > > WARNING: CPU: 0 PID: 1 at arch/x86/mm/pti.c:256 pti_clone_pgtable+0x298/0x2dc > > WARNING: CPU: 0 PID: 1 at arch/x86/mm/pti.c:394 pti_clone_pgtable+0x29a/0x2dc > > The backtraces are repeated multiple times. > > Please see > > https://kerneltests.org/builders/qemu-x86-master/builds/253/steps/qemubuildcommand/logs/stdio > > for complete logs. Could you try the below patch? If that don't work, could you provide the .config, I'm assuming that'll work with the bits I grabbed last time. --- diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c index bfdf5f45b137..bec53f127c0d 100644 --- a/arch/x86/mm/pti.c +++ b/arch/x86/mm/pti.c @@ -634,14 +634,8 @@ void __init pti_init(void) } #endif - pti_clone_user_shared(); - /* Undo all global bits from the init pagetables in head_64.S: */ pti_set_kernel_image_nonglobal(); - /* Replace some of the global bits just for shared entry text: */ - pti_clone_entry_text(); - pti_setup_espfix64(); - pti_setup_vsyscall(); } /* @@ -659,7 +653,12 @@ void pti_finalize(void) * We need to clone everything (again) that maps parts of the * kernel image. */ + pti_clone_user_shared(); + pti_clone_entry_text(); + pti_setup_espfix64(); + pti_setup_vsyscall(); + pti_clone_kernel_text(); debug_checkwx_user();
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