diff options
Diffstat (limited to '0051-x86-entry-don-t-clear-DF-when-raising-UD-for-lack-of.patch')
| -rw-r--r-- | 0051-x86-entry-don-t-clear-DF-when-raising-UD-for-lack-of.patch | 58 |
1 files changed, 0 insertions, 58 deletions
diff --git a/0051-x86-entry-don-t-clear-DF-when-raising-UD-for-lack-of.patch b/0051-x86-entry-don-t-clear-DF-when-raising-UD-for-lack-of.patch deleted file mode 100644 index acefc8e..0000000 --- a/0051-x86-entry-don-t-clear-DF-when-raising-UD-for-lack-of.patch +++ /dev/null @@ -1,58 +0,0 @@ -From 7e636b8a16412d4f0d94b2b24d7ebcd2c749afff Mon Sep 17 00:00:00 2001 -From: Jan Beulich <jbeulich@suse.com> -Date: Thu, 4 Jul 2024 14:14:49 +0200 -Subject: [PATCH 51/56] x86/entry: don't clear DF when raising #UD for lack of - syscall handler - -While doing so is intentional when invoking the actual callback, to -mimic a hard-coded SYCALL_MASK / FMASK MSR, the same should not be done -when no handler is available and hence #UD is raised. - -Fixes: ca6fcf4321b3 ("x86/pv: Inject #UD for missing SYSCALL callbacks") -Reported-by: Andrew Cooper <andrew.cooper3@citrix.com> -Signed-off-by: Jan Beulich <jbeulich@suse.com> -Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> -master commit: d2fe9ab3048d503869ec81bc49db07e55a4a2386 -master date: 2024-07-02 12:01:21 +0200 ---- - xen/arch/x86/x86_64/entry.S | 12 +++++++++++- - 1 file changed, 11 insertions(+), 1 deletion(-) - -diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S -index 054fcb225f..d3def49ea3 100644 ---- a/xen/arch/x86/x86_64/entry.S -+++ b/xen/arch/x86/x86_64/entry.S -@@ -38,6 +38,14 @@ switch_to_kernel: - setc %cl - leal (,%rcx,TBF_INTERRUPT),%ecx - -+ /* -+ * The PV ABI hardcodes the (guest-inaccessible and virtual) -+ * SYSCALL_MASK MSR such that DF (and nothing else) would be cleared. -+ * Note that the equivalent of IF (VGCF_syscall_disables_events) is -+ * dealt with separately above. -+ */ -+ mov $~X86_EFLAGS_DF, %esi -+ - test %rax, %rax - UNLIKELY_START(z, syscall_no_callback) /* TB_eip == 0 => #UD */ - mov VCPU_trap_ctxt(%rbx), %rdi -@@ -47,12 +55,14 @@ UNLIKELY_START(z, syscall_no_callback) /* TB_eip == 0 => #UD */ - testb $4, X86_EXC_UD * TRAPINFO_sizeof + TRAPINFO_flags(%rdi) - setnz %cl - lea TBF_EXCEPTION(, %rcx, TBF_INTERRUPT), %ecx -+ or $~0, %esi /* Don't clear DF */ - UNLIKELY_END(syscall_no_callback) - - movq %rax,TRAPBOUNCE_eip(%rdx) - movb %cl,TRAPBOUNCE_flags(%rdx) - call create_bounce_frame -- andl $~X86_EFLAGS_DF,UREGS_eflags(%rsp) -+ /* Conditionally clear DF */ -+ and %esi, UREGS_eflags(%rsp) - /* %rbx: struct vcpu */ - test_all_events: - ASSERT_NOT_IN_ATOMIC --- -2.45.2 - |