From 9f9116406120638b4d8db3831ffbc430dd2e1e95 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Tue, 25 Jul 2023 02:03:29 +0300 Subject: [PATCH] x86/traps: Fix load_unaligned_zeropad() handling for shared TDX memory Commit c4e34dd99f2e ("x86: simplify load_unaligned_zeropad() implementation") changes how exceptions around load_unaligned_zeropad() handled. The kernel now uses the fault_address in fixup_exception() to verify the address calculations for the load_unaligned_zeropad(). It works fine for #PF, but breaks on #VE since no fault address is passed down to fixup_exception(). Propagating ve_info.gla down to fixup_exception() resolves the issue. See commit 1e7769653b06 ("x86/tdx: Handle load_unaligned_zeropad() page-cross to a shared page") for more context. Signed-off-by: Kirill A. Shutemov Reported-by: Michael Kelley Fixes: c4e34dd99f2e ("x86: simplify load_unaligned_zeropad() implementation") Acked-by: Dave Hansen Signed-off-by: Linus Torvalds --- arch/x86/kernel/traps.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 58b1f20..4a817d2 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -697,9 +697,10 @@ static bool try_fixup_enqcmd_gp(void) } static bool gp_try_fixup_and_notify(struct pt_regs *regs, int trapnr, - unsigned long error_code, const char *str) + unsigned long error_code, const char *str, + unsigned long address) { - if (fixup_exception(regs, trapnr, error_code, 0)) + if (fixup_exception(regs, trapnr, error_code, address)) return true; current->thread.error_code = error_code; @@ -759,7 +760,7 @@ DEFINE_IDTENTRY_ERRORCODE(exc_general_protection) goto exit; } - if (gp_try_fixup_and_notify(regs, X86_TRAP_GP, error_code, desc)) + if (gp_try_fixup_and_notify(regs, X86_TRAP_GP, error_code, desc, 0)) goto exit; if (error_code) @@ -1357,17 +1358,20 @@ DEFINE_IDTENTRY(exc_device_not_available) #define VE_FAULT_STR "VE fault" -static void ve_raise_fault(struct pt_regs *regs, long error_code) +static void ve_raise_fault(struct pt_regs *regs, long error_code, + unsigned long address) { if (user_mode(regs)) { gp_user_force_sig_segv(regs, X86_TRAP_VE, error_code, VE_FAULT_STR); return; } - if (gp_try_fixup_and_notify(regs, X86_TRAP_VE, error_code, VE_FAULT_STR)) + if (gp_try_fixup_and_notify(regs, X86_TRAP_VE, error_code, + VE_FAULT_STR, address)) { return; + } - die_addr(VE_FAULT_STR, regs, error_code, 0); + die_addr(VE_FAULT_STR, regs, error_code, address); } /* @@ -1431,7 +1435,7 @@ DEFINE_IDTENTRY(exc_virtualization_exception) * it successfully, treat it as #GP(0) and handle it. */ if (!tdx_handle_virt_exception(regs, &ve)) - ve_raise_fault(regs, 0); + ve_raise_fault(regs, 0, ve.gla); cond_local_irq_disable(regs); } -- 2.7.4