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[209.132.180.67]) by mx.google.com with ESMTP id 128si21782424oih.78.2020.01.22.13.12.21; Wed, 22 Jan 2020 13:12:34 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=AcSbf+qL; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728998AbgAVVKp (ORCPT + 99 others); Wed, 22 Jan 2020 16:10:45 -0500 Received: from mail-pj1-f67.google.com ([209.85.216.67]:39327 "EHLO mail-pj1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725827AbgAVVKo (ORCPT ); Wed, 22 Jan 2020 16:10:44 -0500 Received: by mail-pj1-f67.google.com with SMTP id e11so124772pjt.4 for ; Wed, 22 Jan 2020 13:10:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:subject:cc:to:in-reply-to:references:message-id :mime-version:content-transfer-encoding; bh=ZZ5b/mbw3dSCyUguJZVK2QM63WHkMGA0/u35MRIw+xo=; b=AcSbf+qLCffvaX4kcM1u5cVFg+cBUsitPXNatz5Wa6KDwXvW7JR5WCRlauiNarwGB7 X/H8QHOJgkc0KBiefkxrqD2Wae1KQFGYDmWaNUVMZv92Mih36aGxQa6uab1nBj1zrWUQ +UpXKEJYfYlMZNOP5fe3TrnGtTh0PkfKZ6BbKsSaZebpAkpA0f9TbN81pW1ljDXTpDRc slhSxDKxsLwHJUnzxJy3UZ5FiEteukbKEGck4ekSTbTc6zQvPDqJDKciMZvX4V2Xm0nI H9jDW8YteqOIPm5qeEkt72/Z6li3gKjBa2pXWEOG0Uk8u/SnR8vAIdKJF5xYwgc0u1CY 92bg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:subject:cc:to:in-reply-to:references :message-id:mime-version:content-transfer-encoding; bh=ZZ5b/mbw3dSCyUguJZVK2QM63WHkMGA0/u35MRIw+xo=; b=ZAjCj4ZJPRlQViZRuI3js309LQ9Q6aHQ8HZg6FGtE5VlDqF17WLv6rF5ygWVhbyvTb iXw9ZpLmXTVpmGMa/mvhEmBNykxG139I6/vV7vxf8DvrcIIf+M/Ij6+RW0CGz9f25kwh CkaaWS1SxBqIs9mlQgdjI46oxbpx30+oEI0FZavlZSmwDUsX/pwZAuX6i1TccaopmLHJ dMSnxHSLxnqxrxxSxXuAqNrMIUsfc70rkMt6Cy6yCgdFmLDC8nQ4PTBqa8xub/6Tw38V JC3xmQR4EAbfmYMqf4VtesJH0oc42bjsLJk2xrHqrHjm5YOkP2YSYNvLEFdRkK7er5Y0 vLvg== X-Gm-Message-State: APjAAAWU8LMkOgkIYn0+iL8l+pGr2hHMzB8Qb82CtIyfoHRMu6shWzhk kqn/m6k4PKeOI3lmzGQNdubg+w== X-Received: by 2002:a17:902:b087:: with SMTP id p7mr13443167plr.10.1579727443858; Wed, 22 Jan 2020 13:10:43 -0800 (PST) Received: from localhost ([2620:0:1000:2514:7f69:cd98:a2a2:a03d]) by smtp.gmail.com with ESMTPSA id v4sm47906316pfn.181.2020.01.22.13.10.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Jan 2020 13:10:43 -0800 (PST) Date: Wed, 22 Jan 2020 13:10:43 -0800 (PST) X-Google-Original-Date: Wed, 22 Jan 2020 13:07:04 PST (-0800) From: Palmer Dabbelt X-Google-Original-From: Palmer Dabbelt Subject: Re: [PATCH 1/2] riscv: mm: add support for CONFIG_DEBUG_VIRTUAL CC: Paul Walmsley , aou@eecs.berkeley.edu, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, zong.li@sifive.com To: zong.li@sifive.com In-Reply-To: <20200102031240.44484-2-zong.li@sifive.com> References: <20200102031240.44484-2-zong.li@sifive.com> <20200102031240.44484-1-zong.li@sifive.com> Message-ID: Mime-Version: 1.0 (MHng) Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 01 Jan 2020 19:12:39 PST (-0800), zong.li@sifive.com wrote: > This patch implements CONFIG_DEBUG_VIRTUAL to do additional checks on > virt_to_phys and __pa_symbol calls. virt_to_phys used for linear mapping > check, and __pa_symbol used for kernel symbol check. In current RISC-V, > kernel image maps to linear mapping area. If CONFIG_DEBUG_VIRTUAL is > disable, these two functions calculate the offset on the address feded > directly without any checks. > > The result of test_debug_virtual as follows: > > [ 0.358456] ------------[ cut here ]------------ > [ 0.358738] virt_to_phys used for non-linear address: (____ptrval____) (0xffffffd000000000) > [ 0.359174] WARNING: CPU: 0 PID: 1 at arch/riscv/mm/physaddr.c:16 __virt_to_phys+0x3c/0x50 > [ 0.359409] Modules linked in: > [ 0.359630] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.5.0-rc3-00002-g5133c5c0ca13 #57 > [ 0.359861] epc: ffffffe000253d1a ra : ffffffe000253d1a sp : ffffffe03aa87da0 > [ 0.360019] gp : ffffffe000ae03b0 tp : ffffffe03aa88000 t0 : ffffffe000af2660 > [ 0.360175] t1 : 0000000000000064 t2 : 00000000000000b7 s0 : ffffffe03aa87dc0 > [ 0.360330] s1 : ffffffd000000000 a0 : 000000000000004f a1 : 0000000000000000 > [ 0.360492] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffe000a84358 > [ 0.360672] a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000000000000 > [ 0.360876] s2 : ffffffe000ae0600 s3 : ffffffe00000fc7c s4 : ffffffe0000224b0 > [ 0.361067] s5 : ffffffe000030890 s6 : ffffffe000022470 s7 : 0000000000000008 > [ 0.361267] s8 : ffffffe0000002c4 s9 : ffffffe000ae0640 s10: ffffffe000ae0630 > [ 0.361453] s11: 0000000000000000 t3 : 0000000000000000 t4 : 000000000001e6d0 > [ 0.361636] t5 : ffffffe000ae0a18 t6 : ffffffe000aee54e > [ 0.361806] status: 0000000000000120 badaddr: 0000000000000000 cause: 0000000000000003 > [ 0.362056] ---[ end trace aec0bf78d4978122 ]--- > [ 0.362404] PA: 0xfffffff080200000 for VA: 0xffffffd000000000 > [ 0.362607] PA: 0x00000000baddd2d0 for VA: 0xffffffe03abdd2d0 > > Signed-off-by: Zong Li Thanks. Looks like patch 2 landed in Linus' tree as part of 5.5, but this one didn't. I've taken it on to for-next. > --- > arch/riscv/Kconfig | 1 + > arch/riscv/include/asm/page.h | 16 +++++++++++++-- > arch/riscv/mm/Makefile | 2 ++ > arch/riscv/mm/physaddr.c | 37 +++++++++++++++++++++++++++++++++++ > 4 files changed, 54 insertions(+), 2 deletions(-) > create mode 100644 arch/riscv/mm/physaddr.c > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index d8efbaa78d67..7f268816be5b 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -57,6 +57,7 @@ config RISCV > select GENERIC_ARCH_TOPOLOGY if SMP > select ARCH_HAS_PTE_SPECIAL > select ARCH_HAS_MMIOWB > + select ARCH_HAS_DEBUG_VIRTUAL > select HAVE_EBPF_JIT if 64BIT > select EDAC_SUPPORT > select ARCH_HAS_GIGANTIC_PAGE > diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h > index ac699246ae7e..8ca1930caa44 100644 > --- a/arch/riscv/include/asm/page.h > +++ b/arch/riscv/include/asm/page.h > @@ -100,8 +100,20 @@ extern unsigned long pfn_base; > extern unsigned long max_low_pfn; > extern unsigned long min_low_pfn; > > -#define __pa(x) ((unsigned long)(x) - va_pa_offset) > -#define __va(x) ((void *)((unsigned long) (x) + va_pa_offset)) > +#define __pa_to_va_nodebug(x) ((void *)((unsigned long) (x) + va_pa_offset)) > +#define __va_to_pa_nodebug(x) ((unsigned long)(x) - va_pa_offset) > + > +#ifdef CONFIG_DEBUG_VIRTUAL > +extern phys_addr_t __virt_to_phys(unsigned long x); > +extern phys_addr_t __phys_addr_symbol(unsigned long x); > +#else > +#define __virt_to_phys(x) __va_to_pa_nodebug(x) > +#define __phys_addr_symbol(x) __va_to_pa_nodebug(x) > +#endif /* CONFIG_DEBUG_VIRTUAL */ > + > +#define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0)) > +#define __pa(x) __virt_to_phys((unsigned long)(x)) > +#define __va(x) ((void *)__pa_to_va_nodebug((phys_addr_t)(x))) > > #define phys_to_pfn(phys) (PFN_DOWN(phys)) > #define pfn_to_phys(pfn) (PFN_PHYS(pfn)) > diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile > index a1bd95c8047a..7de157ecfb77 100644 > --- a/arch/riscv/mm/Makefile > +++ b/arch/riscv/mm/Makefile > @@ -15,3 +15,5 @@ ifeq ($(CONFIG_MMU),y) > obj-$(CONFIG_SMP) += tlbflush.o > endif > obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o > + > +obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o > diff --git a/arch/riscv/mm/physaddr.c b/arch/riscv/mm/physaddr.c > new file mode 100644 > index 000000000000..e8e4dcd39fed > --- /dev/null > +++ b/arch/riscv/mm/physaddr.c > @@ -0,0 +1,37 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include > +#include > +#include > +#include > +#include > + > +phys_addr_t __virt_to_phys(unsigned long x) > +{ > + phys_addr_t y = x - PAGE_OFFSET; > + > + /* > + * Boundary checking aginst the kernel linear mapping space. > + */ > + WARN(y >= KERN_VIRT_SIZE, > + "virt_to_phys used for non-linear address: %pK (%pS)\n", > + (void *)x, (void *)x); > + > + return __va_to_pa_nodebug(x); > +} > +EXPORT_SYMBOL(__virt_to_phys); > + > +phys_addr_t __phys_addr_symbol(unsigned long x) > +{ > + unsigned long kernel_start = (unsigned long)PAGE_OFFSET; > + unsigned long kernel_end = (unsigned long)_end; > + > + /* > + * Boundary checking aginst the kernel image mapping. > + * __pa_symbol should only be used on kernel symbol addresses. > + */ > + VIRTUAL_BUG_ON(x < kernel_start || x > kernel_end); > + > + return __va_to_pa_nodebug(x); > +} > +EXPORT_SYMBOL(__phys_addr_symbol);