Patch "selftests/x86/entry_from_vm86: Add test cases for POPF" has been added to the 4.4-stable tree
Subsystems (3)
This is a note to let you know that I've just added the patch titled
selftests/x86/entry_from_vm86: Add test cases for POPF
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
selftests-x86-entry_from_vm86-add-test-cases-for-popf.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.
Quoted 1 line
From
78393fdde2a456cafa414b171c90f26a3df98b20Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <[email protected]>
Date: Tue, 13 Mar 2018 22:03:11 -0700
Subject: selftests/x86/entry_from_vm86: Add test cases for POPF
From: Andy Lutomirski <[email protected]>
commit 78393fdde2a456cafa414b171c90f26a3df98b20 upstream.
POPF is currently broken -- add tests to catch the error. This results in:
[RUN] POPF with VIP set and IF clear from vm86 mode
[INFO] Exited vm86 mode due to STI
[FAIL] Incorrect return reason (started at eip = 0xd, ended at eip = 0xf)
because POPF currently fails to check IF before reporting a pending interrupt.
This patch also makes the FAIL message a bit more informative.
--- tools/testing/selftests/x86/entry_from_vm86.c | 30 +++++++++++++++++++++++--- 1 file changed, 27 insertions(+), 3 deletions(-)
tools/testing/selftests/x86/entry_from_vm86.c +27 -3
@@ -95,6 +95,10 @@ asm ("int3\n\t" "vmcode_int80:\n\t" "int $0x80\n\t" +"vmcode_popf_hlt:\n\t" +"push %ax\n\t" +"popf\n\t" +"hlt\n\t" "vmcode_umip:\n\t" /* addressing via displacements */ "smsw (2052)\n\t"
@@ -124,8 +128,8 @@ asm (extern unsigned char vmcode[], end_vmcode[];extern unsigned char vmcode_bound[], vmcode_sysenter[], vmcode_syscall[], - vmcode_sti[], vmcode_int3[], vmcode_int80[], vmcode_umip[], - vmcode_umip_str[], vmcode_umip_sldt[]; + vmcode_sti[], vmcode_int3[], vmcode_int80[], vmcode_popf_hlt[], + vmcode_umip[], vmcode_umip_str[], vmcode_umip_sldt[];/* Returns false if the test was skipped. */ static bool do_test(struct vm86plus_struct *v86, unsigned long eip,
@@ -175,7 +179,7 @@ static bool do_test(struct vm86plus_stru (VM86_TYPE(ret) == rettype && VM86_ARG(ret) == retarg)) { printf("[OK]\tReturned correctly\n"); } else { -printf ("[FAIL]\tIncorrect return reason\n" ); +printf ("[FAIL]\tIncorrect return reason (started at eip = 0x%lx, ended at eip = 0x%lx)\n" , eip, v86->regs.eip); nerrs++; }
@@ -264,6 +268,9 @@ int main(void) v86.regs.ds = load_addr /16 ; v86.regs.es = load_addr /16 ; +/* Use the end of the page as our stack. */ + v86.regs.esp =4096 ; +assert ((v86.regs.cs &3 ) ==0 );/* Looks like RPL = 0 */ /* #BR -- should deliver SIG??? */
@@ -295,6 +302,23 @@ int main(void) v86.regs.eflags &= ~X86_EFLAGS_IF ;do_test (&v86, vmcode_sti - vmcode,VM86_STI ,0 ,"STI with VIP set" ); +/* POPF with VIP set but IF clear: should not trap */ + v86.regs.eflags =X86_EFLAGS_VIP ; + v86.regs.eax =0 ; +do_test (&v86, vmcode_popf_hlt - vmcode,VM86_UNKNOWN ,0 ,"POPF with VIP set and IF clear" ); + +/* POPF with VIP set and IF set: should trap */ + v86.regs.eflags =X86_EFLAGS_VIP ; + v86.regs.eax =X86_EFLAGS_IF ; +do_test (&v86, vmcode_popf_hlt - vmcode,VM86_STI ,0 ,"POPF with VIP and IF set" ); + +/* POPF with VIP clear and IF set: should not trap */ + v86.regs.eflags =0 ; + v86.regs.eax =X86_EFLAGS_IF ; +do_test (&v86, vmcode_popf_hlt - vmcode,VM86_UNKNOWN ,0 ,"POPF with VIP clear and IF set" ); + + v86.regs.eflags =0 ; +/* INT3 -- should cause #BP */ do_test (&v86, vmcode_int3 - vmcode,VM86_TRAP ,3 ,"INT3" );
Patches currently in stable-queue which might be from [email protected] are
queue-4.4/selftests-x86-add-tests-for-the-str-and-sldt-instructions.patch queue-4.4/x86-vm86-32-fix-popf-emulation.patch queue-4.4/selftests-x86-add-tests-for-user-mode-instruction-prevention.patch queue-4.4/perf-tools-make-perf_event__synthesize_mmap_events-scale.patch queue-4.4/x86-mm-fix-vmalloc_fault-to-use-pxd_large.patch queue-4.4/selftests-x86-entry_from_vm86-add-test-cases-for-popf.patch queue-4.4/selftests-x86-entry_from_vm86-exit-with-1-if-we-fail.patch