From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-x22f.google.com (mail-wm0-x22f.google.com [IPv6:2a00:1450:400c:c09::22f]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id B05138032B for ; Mon, 6 Mar 2017 09:32:28 -0800 (PST) Received: by mail-wm0-x22f.google.com with SMTP id v186so70022605wmd.0 for ; Mon, 06 Mar 2017 09:32:28 -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=3UR+Rrzng3KpHgT/YQ9RaMZOW9xJl68q1HYUq2t/fO8=; b=CV6ybr3uWQFaLIAgb9cAO7w+wELNruOl1a23MOycbwUgpOtrKLKbj+zy5TVyop/O2X QivLQadk+kA+4EWUuXQAjvF3yw4CrWy1iH6EySSubwvR3v3GJymRd1cZJk4l8o9i95qm axVvN0FLnBjiXqhpTUgwVOgjom5DeSiqVToKg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=3UR+Rrzng3KpHgT/YQ9RaMZOW9xJl68q1HYUq2t/fO8=; b=oS+MS6kShWqthQBEeERMRulqZAGtNnX0Rj8QmK6V97cWxu21iYKyf1rebw2wYPhTlp uePsY5KRwVZHxEZoTrJ3WovpKRy0C4HoTEnt/0uaaoak7OHTMLrDf0OaXGPXQn9r803N 3KIx7iS/RbVNBY7rb2aEDDXVvoUP/Fx8L9lnldiU2c1/yEq/wM1wnOTvRXY7JCI40Wcu RaNErmmPfvw+bZeEs0955rIgScQZBuP6BtdsNoCsSD2p3YhhzUfw6AoQnVk2dxYWZow5 ypObajFRRGazAly2cjst5NYAom5OJ4jgM8ovi229rtH9899+2zogOgok3BUqzIotodZH /OQg== X-Gm-Message-State: AMke39lcc0//bpp1fojy5g+6HBT1yZbm9D6IDPPxJS1g5hp8u0b0kx7tEhtNw/d0g+yiDHJ7 X-Received: by 10.28.93.68 with SMTP id r65mr15360834wmb.133.1488821547189; Mon, 06 Mar 2017 09:32:27 -0800 (PST) Received: from ards-macbook-pro.c.hoisthospitality.com ([109.74.48.129]) by smtp.gmail.com with ESMTPSA id 136sm15704335wmg.12.2017.03.06.09.32.24 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 06 Mar 2017 09:32:26 -0800 (PST) From: Ard Biesheuvel To: edk2-devel@lists.01.org, leif.lindholm@linaro.org Cc: lersek@redhat.com, Ard Biesheuvel Date: Mon, 6 Mar 2017 18:32:14 +0100 Message-Id: <1488821535-14795-4-git-send-email-ard.biesheuvel@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1488821535-14795-1-git-send-email-ard.biesheuvel@linaro.org> References: <1488821535-14795-1-git-send-email-ard.biesheuvel@linaro.org> Subject: [PATCH v3 3/4] ArmPkg/CpuDxe ARM: honour RO/XP attributes in SetMemoryAttributes() X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 06 Mar 2017 17:32:29 -0000 Enable the use of strict memory permissions on ARM by processing the EFI_MEMORY_RO and EFI_MEMORY_XP rather than ignoring them. As before, calls to CpuArchProtocol::SetMemoryAttributes that only set RO/XP bits will preserve the cacheability attributes. Permissions attributes are not preserved when setting the memory type only: the way the memory permission attributes are defined does not allows for that, and so this situation does not deviate from other architectures. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel --- ArmPkg/Drivers/CpuDxe/Arm/Mmu.c | 178 ++++++++++---------- 1 file changed, 86 insertions(+), 92 deletions(-) diff --git a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c index a2993cf16a35..d3c307f48317 100644 --- a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c +++ b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c @@ -19,6 +19,13 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. #include #include "CpuDxe.h" +#define CACHE_ATTRIBUTE_MASK (EFI_MEMORY_UC | \ + EFI_MEMORY_WC | \ + EFI_MEMORY_WT | \ + EFI_MEMORY_WB | \ + EFI_MEMORY_UCE | \ + EFI_MEMORY_WP) + // First Level Descriptors typedef UINT32 ARM_FIRST_LEVEL_DESCRIPTOR; @@ -374,50 +381,48 @@ UpdatePageEntries ( // EntryMask: bitmask of values to change (1 = change this value, 0 = leave alone) // EntryValue: values at bit positions specified by EntryMask - EntryMask = TT_DESCRIPTOR_PAGE_TYPE_MASK; - EntryValue = TT_DESCRIPTOR_PAGE_TYPE_PAGE; - // Although the PI spec is unclear on this the GCD guarantees that only - // one Attribute bit is set at a time, so we can safely use a switch statement - switch (Attributes) { - case EFI_MEMORY_UC: - // modify cacheability attributes - EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK; - // map to strongly ordered - EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_STRONGLY_ORDERED; // TEX[2:0] = 0, C=0, B=0 - break; - - case EFI_MEMORY_WC: - // modify cacheability attributes - EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK; - // map to normal non-cachable - EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_NON_CACHEABLE; // TEX [2:0]= 001 = 0x2, B=0, C=0 - break; - - case EFI_MEMORY_WT: - // modify cacheability attributes - EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK; - // write through with no-allocate - EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_WRITE_THROUGH_NO_ALLOC; // TEX [2:0] = 0, C=1, B=0 - break; - - case EFI_MEMORY_WB: - // modify cacheability attributes - EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK; - // write back (with allocate) - EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_WRITE_BACK_ALLOC; // TEX [2:0] = 001, C=1, B=1 - break; + EntryMask = TT_DESCRIPTOR_PAGE_TYPE_MASK | TT_DESCRIPTOR_PAGE_AP_MASK; + if ((Attributes & EFI_MEMORY_XP) != 0) { + EntryValue = TT_DESCRIPTOR_PAGE_TYPE_PAGE_XN; + } else { + EntryValue = TT_DESCRIPTOR_PAGE_TYPE_PAGE; + } - case EFI_MEMORY_WP: - case EFI_MEMORY_XP: - case EFI_MEMORY_UCE: - // cannot be implemented UEFI definition unclear for ARM - // Cause a page fault if these ranges are accessed. - EntryValue = TT_DESCRIPTOR_PAGE_TYPE_FAULT; - DEBUG ((EFI_D_PAGE, "SetMemoryAttributes(): setting page %lx with unsupported attribute %x will page fault on access\n", BaseAddress, Attributes)); - break; + // Although the PI spec is unclear on this, the GCD guarantees that only + // one Attribute bit is set at a time, so the order of the conditionals below + // is irrelevant. If no memory attribute is specified, we preserve whatever + // memory type is set in the page tables, and update the permission attributes + // only. + if (Attributes & EFI_MEMORY_UC) { + // modify cacheability attributes + EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK; + // map to strongly ordered + EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_STRONGLY_ORDERED; // TEX[2:0] = 0, C=0, B=0 + } else if (Attributes & EFI_MEMORY_WC) { + // modify cacheability attributes + EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK; + // map to normal non-cachable + EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_NON_CACHEABLE; // TEX [2:0]= 001 = 0x2, B=0, C=0 + } else if (Attributes & EFI_MEMORY_WT) { + // modify cacheability attributes + EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK; + // write through with no-allocate + EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_WRITE_THROUGH_NO_ALLOC; // TEX [2:0] = 0, C=1, B=0 + } else if (Attributes & EFI_MEMORY_WB) { + // modify cacheability attributes + EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK; + // write back (with allocate) + EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_WRITE_BACK_ALLOC; // TEX [2:0] = 001, C=1, B=1 + } else if (Attributes & CACHE_ATTRIBUTE_MASK) { + // catch unsupported memory type attributes + ASSERT (FALSE); + return EFI_UNSUPPORTED; + } - default: - return EFI_UNSUPPORTED; + if ((Attributes & EFI_MEMORY_RO) != 0) { + EntryValue |= TT_DESCRIPTOR_PAGE_AP_RO_RO; + } else { + EntryValue |= TT_DESCRIPTOR_PAGE_AP_RW_RW; } // Obtain page table base @@ -520,53 +525,49 @@ UpdateSectionEntries ( // EntryValue: values at bit positions specified by EntryMask // Make sure we handle a section range that is unmapped - EntryMask = TT_DESCRIPTOR_SECTION_TYPE_MASK; + EntryMask = TT_DESCRIPTOR_SECTION_TYPE_MASK | TT_DESCRIPTOR_SECTION_XN_MASK | + TT_DESCRIPTOR_SECTION_AP_MASK; EntryValue = TT_DESCRIPTOR_SECTION_TYPE_SECTION; - // Although the PI spec is unclear on this the GCD guarantees that only - // one Attribute bit is set at a time, so we can safely use a switch statement - switch(Attributes) { - case EFI_MEMORY_UC: - // modify cacheability attributes - EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK; - // map to strongly ordered - EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_STRONGLY_ORDERED; // TEX[2:0] = 0, C=0, B=0 - break; - - case EFI_MEMORY_WC: - // modify cacheability attributes - EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK; - // map to normal non-cachable - EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_NON_CACHEABLE; // TEX [2:0]= 001 = 0x2, B=0, C=0 - break; - - case EFI_MEMORY_WT: - // modify cacheability attributes - EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK; - // write through with no-allocate - EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_THROUGH_NO_ALLOC; // TEX [2:0] = 0, C=1, B=0 - break; - - case EFI_MEMORY_WB: - // modify cacheability attributes - EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK; - // write back (with allocate) - EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_BACK_ALLOC; // TEX [2:0] = 001, C=1, B=1 - break; - - case EFI_MEMORY_WP: - case EFI_MEMORY_XP: - case EFI_MEMORY_RP: - case EFI_MEMORY_UCE: - // cannot be implemented UEFI definition unclear for ARM - // Cause a page fault if these ranges are accessed. - EntryValue = TT_DESCRIPTOR_SECTION_TYPE_FAULT; - DEBUG ((EFI_D_PAGE, "SetMemoryAttributes(): setting section %lx with unsupported attribute %x will page fault on access\n", BaseAddress, Attributes)); - break; + // Although the PI spec is unclear on this, the GCD guarantees that only + // one Attribute bit is set at a time, so the order of the conditionals below + // is irrelevant. If no memory attribute is specified, we preserve whatever + // memory type is set in the page tables, and update the permission attributes + // only. + if (Attributes & EFI_MEMORY_UC) { + // modify cacheability attributes + EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK; + // map to strongly ordered + EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_STRONGLY_ORDERED; // TEX[2:0] = 0, C=0, B=0 + } else if (Attributes & EFI_MEMORY_WC) { + // modify cacheability attributes + EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK; + // map to normal non-cachable + EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_NON_CACHEABLE; // TEX [2:0]= 001 = 0x2, B=0, C=0 + } else if (Attributes & EFI_MEMORY_WT) { + // modify cacheability attributes + EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK; + // write through with no-allocate + EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_THROUGH_NO_ALLOC; // TEX [2:0] = 0, C=1, B=0 + } else if (Attributes & EFI_MEMORY_WB) { + // modify cacheability attributes + EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK; + // write back (with allocate) + EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_BACK_ALLOC; // TEX [2:0] = 001, C=1, B=1 + } else if (Attributes & CACHE_ATTRIBUTE_MASK) { + // catch unsupported memory type attributes + ASSERT (FALSE); + return EFI_UNSUPPORTED; + } + if (Attributes & EFI_MEMORY_RO) { + EntryValue |= TT_DESCRIPTOR_SECTION_AP_RO_RO; + } else { + EntryValue |= TT_DESCRIPTOR_SECTION_AP_RW_RW; + } - default: - return EFI_UNSUPPORTED; + if (Attributes & EFI_MEMORY_XP) { + EntryValue |= TT_DESCRIPTOR_SECTION_XN_MASK; } // obtain page table base @@ -697,13 +698,6 @@ SetMemoryAttributes ( return EFI_SUCCESS; } - // - // Ignore invocations that only modify permission bits - // - if ((Attributes & EFI_MEMORY_CACHETYPE_MASK) == 0) { - return EFI_SUCCESS; - } - FlushTlbs = FALSE; while (Length > 0) { if ((BaseAddress % TT_DESCRIPTOR_SECTION_SIZE == 0) && -- 2.7.4