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[209.132.180.67]) by mx.google.com with ESMTP id f65si8847519pff.29.2016.01.27.02.56.56; Wed, 27 Jan 2016 02:56:56 -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; 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; dkim=pass header.i=@linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754699AbcA0K4t (ORCPT + 30 others); Wed, 27 Jan 2016 05:56:49 -0500 Received: from mail-wm0-f47.google.com ([74.125.82.47]:38330 "EHLO mail-wm0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754466AbcA0Kzj (ORCPT ); Wed, 27 Jan 2016 05:55:39 -0500 Received: by mail-wm0-f47.google.com with SMTP id p63so20182778wmp.1 for ; Wed, 27 Jan 2016 02:55:39 -0800 (PST) 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; bh=4ciguHX7w81hoRFuOdk9mBU3h5/Zf6w4q9oT6TWAGWc=; b=XNjn627Ouiv5StEMkVuYmyi+QK724JgHez1+fWSsjDVoRD3ZlzJnyz054Vu08J+aNL BSW87DoR/H2WyMRC/yhrAtzGLqNFhYmaGa4TiwnG8MTStKv7/NCb1op45F+wKHFE0Kno Jifdbvyj9n2BlZn5xE6zABFye6Wrpbchy63TY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=4ciguHX7w81hoRFuOdk9mBU3h5/Zf6w4q9oT6TWAGWc=; b=UYOaWDRe5W5xxT6nIWQEMUcsPyFHJPASe/EffZYnwVs7S1WMOccXqEjSZfu0KrOte4 m1sZnOQpjrz/RcxQ37x8hq0ApvSQPftMHscfYkg8vM3AXIyu+aRq4DHpVSUBOGaK4+0g HOf1jkb1WVpga6DVymt/7Bzt2aIJYbRFvc8Qmtci4dyHXCvmRNLUXp+QOrJ3rqasFrhV k25HFyFh+FbHHtxCEQLdrgIxx/GYEtMoj8c9WaAo+yUSEuX2YCzHHT3Ugtp9KzDgguzX 9G1FS4+W9nKokIrX7fjOI1eC3YYTT8pP/BTY0Ri4tvtmSYx2ridu6tYAyd1c95EuUdSl maog== X-Gm-Message-State: AG10YOTs9JFwQ/yOuIQLaPJPa+Ovu+emDHEgDJQo/JAWEIZL6QtDB/C0fZfveoSUooudhfII X-Received: by 10.28.17.8 with SMTP id 8mr27552513wmr.65.1453892138528; Wed, 27 Jan 2016 02:55:38 -0800 (PST) Received: from localhost.localdomain ([195.55.142.58]) by smtp.gmail.com with ESMTPSA id x186sm1199196wmg.19.2016.01.27.02.55.36 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 27 Jan 2016 02:55:37 -0800 (PST) From: Ard Biesheuvel To: akpm@linux-foundation.org, linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, x86@kernel.org, hpa@zytor.com, heiko.carstens@de.ibm.com, rth@twiddle.net, tony.luck@intel.com, will.deacon@arm.com Cc: deller@gmx.de, Ard Biesheuvel Subject: [PATCH v2 resend 4/6] x86/extable: use generic search and sort routines Date: Wed, 27 Jan 2016 11:55:21 +0100 Message-Id: <1453892123-17973-5-git-send-email-ard.biesheuvel@linaro.org> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1453892123-17973-1-git-send-email-ard.biesheuvel@linaro.org> References: <1453892123-17973-1-git-send-email-ard.biesheuvel@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Replace the arch specific versions of search_extable() and sort_extable() with calls to the generic ones, which now support relative exception tables as well. Acked-by: H. Peter Anvin Signed-off-by: Ard Biesheuvel --- arch/x86/include/asm/uaccess.h | 5 +- arch/x86/mm/extable.c | 106 +------------------- 2 files changed, 4 insertions(+), 107 deletions(-) -- 2.5.0 diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index a4a30e4b2d34..5664bf927264 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -106,9 +106,8 @@ static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, un struct exception_table_entry { int insn, fixup; }; -/* This is not the generic standard exception_table_entry format */ -#define ARCH_HAS_SORT_EXTABLE -#define ARCH_HAS_SEARCH_EXTABLE + +#define ARCH_HAS_RELATIVE_EXTABLE extern int fixup_exception(struct pt_regs *regs); extern int early_fixup_exception(unsigned long *ip); diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c index 903ec1e9c326..0b172b656f43 100644 --- a/arch/x86/mm/extable.c +++ b/arch/x86/mm/extable.c @@ -1,14 +1,9 @@ + #include -#include -#include + #include static inline unsigned long -ex_insn_addr(const struct exception_table_entry *x) -{ - return (unsigned long)&x->insn + x->insn; -} -static inline unsigned long ex_fixup_addr(const struct exception_table_entry *x) { return (unsigned long)&x->fixup + x->fixup; @@ -70,100 +65,3 @@ int __init early_fixup_exception(unsigned long *ip) return 0; } - -/* - * Search one exception table for an entry corresponding to the - * given instruction address, and return the address of the entry, - * or NULL if none is found. - * We use a binary search, and thus we assume that the table is - * already sorted. - */ -const struct exception_table_entry * -search_extable(const struct exception_table_entry *first, - const struct exception_table_entry *last, - unsigned long value) -{ - while (first <= last) { - const struct exception_table_entry *mid; - unsigned long addr; - - mid = ((last - first) >> 1) + first; - addr = ex_insn_addr(mid); - if (addr < value) - first = mid + 1; - else if (addr > value) - last = mid - 1; - else - return mid; - } - return NULL; -} - -/* - * The exception table needs to be sorted so that the binary - * search that we use to find entries in it works properly. - * This is used both for the kernel exception table and for - * the exception tables of modules that get loaded. - * - */ -static int cmp_ex(const void *a, const void *b) -{ - const struct exception_table_entry *x = a, *y = b; - - /* - * This value will always end up fittin in an int, because on - * both i386 and x86-64 the kernel symbol-reachable address - * space is < 2 GiB. - * - * This compare is only valid after normalization. - */ - return x->insn - y->insn; -} - -void sort_extable(struct exception_table_entry *start, - struct exception_table_entry *finish) -{ - struct exception_table_entry *p; - int i; - - /* Convert all entries to being relative to the start of the section */ - i = 0; - for (p = start; p < finish; p++) { - p->insn += i; - i += 4; - p->fixup += i; - i += 4; - } - - sort(start, finish - start, sizeof(struct exception_table_entry), - cmp_ex, NULL); - - /* Denormalize all entries */ - i = 0; - for (p = start; p < finish; p++) { - p->insn -= i; - i += 4; - p->fixup -= i; - i += 4; - } -} - -#ifdef CONFIG_MODULES -/* - * If the exception table is sorted, any referring to the module init - * will be at the beginning or the end. - */ -void trim_init_extable(struct module *m) -{ - /*trim the beginning*/ - while (m->num_exentries && - within_module_init(ex_insn_addr(&m->extable[0]), m)) { - m->extable++; - m->num_exentries--; - } - /*trim the end*/ - while (m->num_exentries && - within_module_init(ex_insn_addr(&m->extable[m->num_exentries-1]), m)) - m->num_exentries--; -} -#endif /* CONFIG_MODULES */