From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Nw2nx-0004oM-5A for qemu-devel@nongnu.org; Sun, 28 Mar 2010 20:26:09 -0400 Received: from [140.186.70.92] (port=47789 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Nw2nv-0004oA-UX for qemu-devel@nongnu.org; Sun, 28 Mar 2010 20:26:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1Nw2nt-00027C-9L for qemu-devel@nongnu.org; Sun, 28 Mar 2010 20:26:07 -0400 Received: from hall.aurel32.net ([88.191.82.174]:38830) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1Nw2ns-000270-2L for qemu-devel@nongnu.org; Sun, 28 Mar 2010 20:26:05 -0400 From: Aurelien Jarno Date: Mon, 29 Mar 2010 02:25:51 +0200 Message-Id: <1269822354-4878-3-git-send-email-aurelien@aurel32.net> In-Reply-To: <1269822354-4878-1-git-send-email-aurelien@aurel32.net> References: <1269822354-4878-1-git-send-email-aurelien@aurel32.net> Subject: [Qemu-devel] [PATCH 2/5] linux-user: fix page_unprotect when host page size > target page size List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Aurelien Jarno When the host page size is bigger that the target one, unprotecting a page should: - mark all the target pages corresponding to the host page as writable - invalidate all tb corresponding to the host page (and not the target page) Signed-off-by: Aurelien Jarno --- exec.c | 45 ++++++++++++++++++++++----------------------- 1 files changed, 22 insertions(+), 23 deletions(-) diff --git a/exec.c b/exec.c index 0916208..1b0fe52 100644 --- a/exec.c +++ b/exec.c @@ -2447,8 +2447,8 @@ int page_check_range(target_ulong start, target_ulong len, int flags) page. Return TRUE if the fault was successfully handled. */ int page_unprotect(target_ulong address, unsigned long pc, void *puc) { - unsigned int page_index, prot, pindex; - PageDesc *p, *p1; + unsigned int prot; + PageDesc *p; target_ulong host_start, host_end, addr; /* Technically this isn't safe inside a signal handler. However we @@ -2456,37 +2456,36 @@ int page_unprotect(target_ulong address, unsigned long pc, void *puc) practice it seems to be ok. */ mmap_lock(); - host_start = address & qemu_host_page_mask; - page_index = host_start >> TARGET_PAGE_BITS; - p1 = page_find(page_index); - if (!p1) { + p = page_find(address >> TARGET_PAGE_BITS); + if (!p) { mmap_unlock(); return 0; } - host_end = host_start + qemu_host_page_size; - p = p1; - prot = 0; - for(addr = host_start;addr < host_end; addr += TARGET_PAGE_SIZE) { - prot |= p->flags; - p++; - } + /* if the page was really writable, then we change its protection back to writable */ - if (prot & PAGE_WRITE_ORG) { - pindex = (address - host_start) >> TARGET_PAGE_BITS; - if (!(p1[pindex].flags & PAGE_WRITE)) { - mprotect((void *)g2h(host_start), qemu_host_page_size, - (prot & PAGE_BITS) | PAGE_WRITE); - p1[pindex].flags |= PAGE_WRITE; + if ((p->flags & PAGE_WRITE_ORG) && !(p->flags & PAGE_WRITE)) { + host_start = address & qemu_host_page_mask; + host_end = host_start + qemu_host_page_size; + + prot = 0; + for (addr = host_start ; addr < host_end ; addr += TARGET_PAGE_SIZE) { + p = page_find(addr >> TARGET_PAGE_BITS); + p->flags |= PAGE_WRITE; + prot |= p->flags; + /* and since the content will be modified, we must invalidate the corresponding translated code. */ - tb_invalidate_phys_page(address, pc, puc); + tb_invalidate_phys_page(addr, pc, puc); #ifdef DEBUG_TB_CHECK - tb_invalidate_check(address); + tb_invalidate_check(addr); #endif - mmap_unlock(); - return 1; } + mprotect((void *)g2h(host_start), qemu_host_page_size, + prot & PAGE_BITS); + + mmap_unlock(); + return 1; } mmap_unlock(); return 0; -- 1.7.0.2