From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D10D4CD98D6 for ; Fri, 12 Jun 2026 15:51:20 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wY49u-00018E-68; Fri, 12 Jun 2026 11:51:02 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wY49q-00017a-JE for qemu-devel@nongnu.org; Fri, 12 Jun 2026 11:51:00 -0400 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wY49o-0008Cw-S7 for qemu-devel@nongnu.org; Fri, 12 Jun 2026 11:50:58 -0400 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id DDFE260008; Fri, 12 Jun 2026 15:50:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E14B61F000E9; Fri, 12 Jun 2026 15:50:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781279455; bh=cCWxnWBTELIri7mBIrY3nW5i67rK3zVx7spuTib8SAk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=HNqovlGo/yD7eLzbzFHTkCnHNDKBAijHpg5taJl1lOKjGfAgNtpiTEz4/B7nsWSoP qk6t5o1rp1+TEc1gsAjisr/AbvoUuZ+oBNO91JLwfRy2DoFNA/9qfotK5266fpupxD +uY7wHw/v5OsF8kRgUmUHdcxVokIlU2PG6BmknBB4eKxCnXJFGCDsGlPsaY8tE39hm yISPKg8LYvvHs8PDguooSEHRdALRSOgl9VY9acFLOdfBwiB6WN0PImS4y0IzHqWkm/ AniNiKFz0n03oE42pHPe+oZSJsOtCZxx7uyQ2ZaPxgpCIxKyFi+1Hq+f2g9JqztQLD lmX5DaxkBcd8Q== From: Helge Deller To: Stefan Hajnoczi , qemu-devel@nongnu.org Cc: Helge Deller , Pierrick Bouvier , Laurent Vivier , Max Filippov , Matt Turner , Richard Henderson Subject: [PULL 4/4] linux-user/xtensa: save/restore FP registers across signal delivery Date: Fri, 12 Jun 2026 17:50:43 +0200 Message-ID: <20260612155043.3552-5-deller@kernel.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260612155043.3552-1-deller@kernel.org> References: <20260612155043.3552-1-deller@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2600:3c04:e001:324:0:1991:8:25; envelope-from=deller@kernel.org; helo=tor.source.kernel.org X-Spam_score_int: -24 X-Spam_score: -2.5 X-Spam_bar: -- X-Spam_report: (-2.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.445, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Matt Turner Add support for saving and restoring f0-f15 across signal delivery. The target_xtensa_xtregs_fp struct carries 32-bit f-regs for cores with XTENSA_OPTION_FP_COPROCESSOR; target_xtensa_xtregs_dfp carries 64-bit f-regs for cores with XTENSA_OPTION_DFP_COPROCESSOR. Lock the xtregs region via lock_user before reading on sigreturn, since sc_xtregs is a user-space pointer that may lie outside the locked sigframe. Signed-off-by: Matt Turner Reviewed-by: Richard Henderson Signed-off-by: Helge Deller --- linux-user/xtensa/signal.c | 96 ++++++++++++++++++++++++++++++++++---- 1 file changed, 88 insertions(+), 8 deletions(-) diff --git a/linux-user/xtensa/signal.c b/linux-user/xtensa/signal.c index ef8b0c3a27..e3f9da322b 100644 --- a/linux-user/xtensa/signal.c +++ b/linux-user/xtensa/signal.c @@ -21,6 +21,7 @@ #include "user-internals.h" #include "signal-common.h" #include "linux-user/trace.h" +#include "target/xtensa/cpu.h" struct target_sigcontext { abi_ulong sc_pc; @@ -43,10 +44,25 @@ struct target_ucontext { target_sigset_t tuc_sigmask; }; +struct target_xtensa_xtregs_fp { + uint32_t f[16]; + uint32_t fcr; + uint32_t fsr; +}; + +struct target_xtensa_xtregs_dfp { + uint64_t f[16]; + uint32_t fcr; + uint32_t fsr; +}; + struct target_rt_sigframe { target_siginfo_t info; struct target_ucontext uc; - /* TODO: xtregs */ + union { + struct target_xtensa_xtregs_fp fp; + struct target_xtensa_xtregs_dfp dfp; + } xtregs; uint8_t retcode[6]; abi_ulong window[4]; }; @@ -107,6 +123,7 @@ static int flush_window_regs(CPUXtensaState *env) } static int setup_sigcontext(struct target_rt_sigframe *frame, + abi_ulong frame_addr, CPUXtensaState *env) { struct target_sigcontext *sc = &frame->uc.tuc_mcontext; @@ -123,8 +140,25 @@ static int setup_sigcontext(struct target_rt_sigframe *frame, for (i = 0; i < 16; ++i) { __put_user(env->regs[i], sc->sc_a + i); } - __put_user(0, &sc->sc_xtregs); - /* TODO: xtregs */ + if (xtensa_option_enabled(env->config, XTENSA_OPTION_DFP_COPROCESSOR)) { + for (i = 0; i < 16; ++i) { + __put_user(env->fregs[i].f64, &frame->xtregs.dfp.f[i]); + } + __put_user(env->uregs[FCR], &frame->xtregs.dfp.fcr); + __put_user(cpu_get_fsr(env), &frame->xtregs.dfp.fsr); + __put_user(frame_addr + offsetof(struct target_rt_sigframe, xtregs), + &sc->sc_xtregs); + } else if (xtensa_option_enabled(env->config, XTENSA_OPTION_FP_COPROCESSOR)) { + for (i = 0; i < 16; ++i) { + __put_user(env->fregs[i].f32[FP_F32_LOW], &frame->xtregs.fp.f[i]); + } + __put_user(env->uregs[FCR], &frame->xtregs.fp.fcr); + __put_user(cpu_get_fsr(env), &frame->xtregs.fp.fsr); + __put_user(frame_addr + offsetof(struct target_rt_sigframe, xtregs), + &sc->sc_xtregs); + } else { + __put_user(0, &sc->sc_xtregs); + } return 1; } @@ -190,7 +224,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, __put_user(0, &frame->uc.tuc_flags); __put_user(0, &frame->uc.tuc_link); target_save_altstack(&frame->uc.tuc_stack, env); - if (!setup_sigcontext(frame, env)) { + if (!setup_sigcontext(frame, frame_addr, env)) { unlock_user_struct(frame, frame_addr, 0); goto give_sigsegv; } @@ -243,8 +277,8 @@ give_sigsegv: force_sigsegv(sig); } -static void restore_sigcontext(CPUXtensaState *env, - struct target_rt_sigframe *frame) +static int restore_sigcontext(CPUXtensaState *env, + struct target_rt_sigframe *frame) { struct target_sigcontext *sc = &frame->uc.tuc_mcontext; uint32_t ps; @@ -266,7 +300,51 @@ static void restore_sigcontext(CPUXtensaState *env, for (i = 0; i < 16; ++i) { __get_user(env->regs[i], sc->sc_a + i); } - /* TODO: xtregs */ + { + abi_ulong xtregs_addr; + + __get_user(xtregs_addr, &sc->sc_xtregs); + if (xtregs_addr) { + if (xtensa_option_enabled(env->config, + XTENSA_OPTION_DFP_COPROCESSOR)) { + struct target_xtensa_xtregs_dfp *xtregs; + uint32_t fcr, fsr; + + xtregs = lock_user(VERIFY_READ, xtregs_addr, + sizeof(*xtregs), 1); + if (!xtregs) { + return 0; + } + for (i = 0; i < 16; ++i) { + __get_user(env->fregs[i].f64, &xtregs->f[i]); + } + __get_user(fcr, &xtregs->fcr); + __get_user(fsr, &xtregs->fsr); + unlock_user(xtregs, xtregs_addr, 0); + cpu_set_fcr(env, fcr); + cpu_set_fsr(env, fsr); + } else if (xtensa_option_enabled(env->config, + XTENSA_OPTION_FP_COPROCESSOR)) { + struct target_xtensa_xtregs_fp *xtregs; + uint32_t fcr, fsr; + + xtregs = lock_user(VERIFY_READ, xtregs_addr, + sizeof(*xtregs), 1); + if (!xtregs) { + return 0; + } + for (i = 0; i < 16; ++i) { + __get_user(env->fregs[i].f32[FP_F32_LOW], &xtregs->f[i]); + } + __get_user(fcr, &xtregs->fcr); + __get_user(fsr, &xtregs->fsr); + unlock_user(xtregs, xtregs_addr, 0); + cpu_set_fcr(env, fcr); + cpu_set_fsr(env, fsr); + } + } + } + return 1; } long do_rt_sigreturn(CPUXtensaState *env) @@ -282,7 +360,9 @@ long do_rt_sigreturn(CPUXtensaState *env) target_to_host_sigset(&set, &frame->uc.tuc_sigmask); set_sigmask(&set); - restore_sigcontext(env, frame); + if (!restore_sigcontext(env, frame)) { + goto badframe; + } target_restore_altstack(&frame->uc.tuc_stack, env); unlock_user_struct(frame, frame_addr, 0); -- 2.54.0