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[172.254.253.57]) by smtp.gmail.com with ESMTPSA id bm7sm3568612qkb.86.2021.11.02.04.07.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 Nov 2021 04:07:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=h74jAt7hxYWJ8vb//ZptaTN1DfaIP6MJ1JsKHfl8Ic0=; b=BZWt8kLBePsFpxw8g79nSKzp6BLk5ZhJztL5mVP3ZGLkJwLRWyRFU8gfgtBEeOts4L w+thPrkljJd/mi6sVVMXKFoZ6OZv/yX/PLoepkfxEerX2+c8vPq7wwigK4TBjNYzKraI bK0vqucqAqi9wVW63DGACU+lpJyfgq/d1vTzE1ArhLA9s/KJiJnOS5O3TddJy5AAtzEq OuZdsFpb6gjxdxbK+EJ0Pmscug26nNZ96NGLGky9Y5JzE32zNJv8K/vXsjC8mWV6N/tQ 9OnmbhHVskd4PYBEpV7lS0VrRENGxxMRzTuVkGU6lfOKcMV8rVH1wrBX0GeI4yKF5A1j FCfg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=h74jAt7hxYWJ8vb//ZptaTN1DfaIP6MJ1JsKHfl8Ic0=; b=AosfJlDKtGSRnzkncgIFPCmg8w8I0mKoHMQCFLEXY67hIdCSOrGxM8G2gYjDSFBgGk Mhv/Cv3aYOG06csyBIQVu6IvXTSgUrIJcW8KbnHeu7Ol1o0EpmxF6H9mdxlzgg0v/RYV lQ+gckeECLADo1edv/5glpnYEQmeTayyXPWIYuJYQRP6T/7ynCjKB5qZnxVjR94PcTtt jRIIya/rxc92+s2s6aj9nLSQ321HKrh+HrhlTEyHs6IrlOKtfUsmhEb211AoZA2OjgtU a3fLLjjnJQXsfySWRYvnEThxhC1pTkbyhk0SxCMrSMeraQFdnc8NjZCDPn9Ov533p6fm OlvQ== X-Gm-Message-State: AOAM531WmHI+NpciZ9C79qJ3CJKAreU3C5NL7riNLzCLm5XKXUQJQuXA gMXIcsMRddaxFvBwlV/6d4zJEzoVrEMywg== X-Google-Smtp-Source: ABdhPJwvbopvusDaafZ0PO6Ob5BeEiFE+qG5EfxdtvAM3n5lqblV7WtJaAQGq4+vVyeHcsgEfgYtbg== X-Received: by 2002:a05:620a:2808:: with SMTP id f8mr6816341qkp.434.1635851273327; Tue, 02 Nov 2021 04:07:53 -0700 (PDT) From: Richard Henderson To: qemu-devel@nongnu.org Subject: [PULL 20/60] linux-user: Add cpu_loop_exit_sigsegv Date: Tue, 2 Nov 2021 07:07:00 -0400 Message-Id: <20211102110740.215699-21-richard.henderson@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211102110740.215699-1-richard.henderson@linaro.org> References: <20211102110740.215699-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2607:f8b0:4864:20::732; envelope-from=richard.henderson@linaro.org; helo=mail-qk1-x732.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, 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: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: pass (identity @linaro.org) X-ZM-MESSAGEID: 1635852711275100001 This is a new interface to be provided by the os emulator for raising SIGSEGV on fault. Use the new record_sigsegv target hook. Reviewed by: Warner Losh Reviewed-by: Philippe Mathieu-Daud=C3=A9 Signed-off-by: Richard Henderson --- include/exec/exec-all.h | 15 +++++++++++++++ accel/tcg/user-exec.c | 33 ++++++++++++++++++--------------- linux-user/signal.c | 30 ++++++++++++++++++++++-------- 3 files changed, 55 insertions(+), 23 deletions(-) diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h index 5dd663c153..f74578500c 100644 --- a/include/exec/exec-all.h +++ b/include/exec/exec-all.h @@ -685,6 +685,21 @@ MMUAccessType adjust_signal_pc(uintptr_t *pc, bool is_= write); bool handle_sigsegv_accerr_write(CPUState *cpu, sigset_t *old_set, uintptr_t host_pc, abi_ptr guest_addr); =20 +/** + * cpu_loop_exit_sigsegv: + * @cpu: the cpu context + * @addr: the guest address of the fault + * @access_type: access was read/write/execute + * @maperr: true for invalid page, false for permission fault + * @ra: host pc for unwinding + * + * Use the TCGCPUOps hook to record cpu state, do guest operating system + * specific things to raise SIGSEGV, and jump to the main cpu loop. + */ +void QEMU_NORETURN cpu_loop_exit_sigsegv(CPUState *cpu, target_ulong addr, + MMUAccessType access_type, + bool maperr, uintptr_t ra); + #else static inline void mmap_lock(void) {} static inline void mmap_unlock(void) {} diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c index a0cba61e83..c4f69908e9 100644 --- a/accel/tcg/user-exec.c +++ b/accel/tcg/user-exec.c @@ -141,35 +141,38 @@ static int probe_access_internal(CPUArchState *env, t= arget_ulong addr, int fault_size, MMUAccessType access_type, bool nonfault, uintptr_t ra) { - int flags; + int acc_flag; + bool maperr; =20 switch (access_type) { case MMU_DATA_STORE: - flags =3D PAGE_WRITE; + acc_flag =3D PAGE_WRITE_ORG; break; case MMU_DATA_LOAD: - flags =3D PAGE_READ; + acc_flag =3D PAGE_READ; break; case MMU_INST_FETCH: - flags =3D PAGE_EXEC; + acc_flag =3D PAGE_EXEC; break; default: g_assert_not_reached(); } =20 - if (!guest_addr_valid_untagged(addr) || - page_check_range(addr, 1, flags) < 0) { - if (nonfault) { - return TLB_INVALID_MASK; - } else { - CPUState *cpu =3D env_cpu(env); - CPUClass *cc =3D CPU_GET_CLASS(cpu); - cc->tcg_ops->tlb_fill(cpu, addr, fault_size, access_type, - MMU_USER_IDX, false, ra); - g_assert_not_reached(); + if (guest_addr_valid_untagged(addr)) { + int page_flags =3D page_get_flags(addr); + if (page_flags & acc_flag) { + return 0; /* success */ } + maperr =3D !(page_flags & PAGE_VALID); + } else { + maperr =3D true; } - return 0; + + if (nonfault) { + return TLB_INVALID_MASK; + } + + cpu_loop_exit_sigsegv(env_cpu(env), addr, access_type, maperr, ra); } =20 int probe_access_flags(CPUArchState *env, target_ulong addr, diff --git a/linux-user/signal.c b/linux-user/signal.c index b816678ba5..135983747d 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -688,9 +688,27 @@ void force_sigsegv(int oldsig) } force_sig(TARGET_SIGSEGV); } - #endif =20 +void cpu_loop_exit_sigsegv(CPUState *cpu, target_ulong addr, + MMUAccessType access_type, bool maperr, uintptr= _t ra) +{ + const struct TCGCPUOps *tcg_ops =3D CPU_GET_CLASS(cpu)->tcg_ops; + + if (tcg_ops->record_sigsegv) { + tcg_ops->record_sigsegv(cpu, addr, access_type, maperr, ra); + } else if (tcg_ops->tlb_fill) { + tcg_ops->tlb_fill(cpu, addr, 0, access_type, MMU_USER_IDX, false, = ra); + g_assert_not_reached(); + } + + force_sig_fault(TARGET_SIGSEGV, + maperr ? TARGET_SEGV_MAPERR : TARGET_SEGV_ACCERR, + addr); + cpu->exception_index =3D EXCP_INTERRUPT; + cpu_loop_exit_restore(cpu, ra); +} + /* abort execution with signal */ static void QEMU_NORETURN dump_core_and_abort(int target_sig) { @@ -806,7 +824,7 @@ static void host_signal_handler(int host_sig, siginfo_t= *info, void *puc) access_type =3D adjust_signal_pc(&pc, is_write); =20 if (host_sig =3D=3D SIGSEGV) { - const struct TCGCPUOps *tcg_ops; + bool maperr =3D true; =20 if (info->si_code =3D=3D SEGV_ACCERR && h2g_valid(host_addr)) { /* If this was a write to a TB protected page, restart. */ @@ -821,18 +839,14 @@ static void host_signal_handler(int host_sig, siginfo= _t *info, void *puc) * which means that we may get ACCERR when we want MAPERR. */ if (page_get_flags(guest_addr) & PAGE_VALID) { - /* maperr =3D false; */ + maperr =3D false; } else { info->si_code =3D SEGV_MAPERR; } } =20 sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL); - - tcg_ops =3D CPU_GET_CLASS(cpu)->tcg_ops; - tcg_ops->tlb_fill(cpu, guest_addr, 0, access_type, - MMU_USER_IDX, false, pc); - g_assert_not_reached(); + cpu_loop_exit_sigsegv(cpu, guest_addr, access_type, maperr, pc= ); } else { sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL); } --=20 2.25.1