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-rw-r--r--source/ap/squashfs-tools/0002-fix_phys_mem_calculation.patch159
1 files changed, 0 insertions, 159 deletions
diff --git a/source/ap/squashfs-tools/0002-fix_phys_mem_calculation.patch b/source/ap/squashfs-tools/0002-fix_phys_mem_calculation.patch
deleted file mode 100644
index 20f9005b..00000000
--- a/source/ap/squashfs-tools/0002-fix_phys_mem_calculation.patch
+++ /dev/null
@@ -1,159 +0,0 @@
-From 55f7ba830d40d438f0b0663a505e0c227fc68b6b Mon Sep 17 00:00:00 2001
-From: Phillip Lougher <phillip@squashfs.org.uk>
-Date: Tue, 10 Jun 2014 21:51:52 +0100
-Subject: [PATCH] mksquashfs: fix phys mem calculation for 32-bit processes on
- PAE/64-bit kernels
-
-When adding the code to base default memory usage on physical memory
-(by default use 25% of physical memory), I made an oversight. I assumed
-the process would be able to address 25% of physical memory.
-
-However, for 32-bit processes running on a PAE kernel or 64-bit kernel,
-25% of physical memory can easily exceed the addressible memory for a
-32-bit process, e.g. if a machine has 24 GB of physical memory, the
-code would asume the process could easily use 6 GB.
-
-A 32-bit process by definition can only address 4 GB (32-bit pointers).
-But, due to the typical kernel/user-space split (1GB/3GB, or 2GB/2GB)
-on PAE kernels, a 32-bit process may only be able to address 2 GB.
-
-So, if Mksquashfs is a 32-bit application running on a PAE/64-bit kernel,
-the code assumes it can address much more memory than it really can, which
-means it runs out of memory.
-
-The fix is to impose a maximum default limit on 32-bit kernels, or
-otherwise to never use a value more than 25% of the address space. If
-we assume the maximum address space is 2 GB, then the maximum becomes
-512 MB. But, given most kernels used the 1GB/3GB split, that may be
-unduely conservative, and 25% of 3 GB (756 MB) may be better. This
-patch compromises on 640 MB, which is mid-way between the 512 MB and 756 MB
-values. It is also the fixed default value previously used by Mksquashfs.
-
-This patch also alters the code which imposes a maximum size. Previously
-it was believed limiting to the physical memory size was adequate. But
-obviously this needs to be updated to take into account a 32-bit process
-may only be able to address 2 GB. In the process I've also taken the
-opportunity to limit all requests to no more than 75% of physical memory.
-
-Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
----
- squashfs-tools/mksquashfs.c | 78 ++++++++++++++++++++++++++++++++++++++++-----
- 1 file changed, 70 insertions(+), 8 deletions(-)
-
-diff --git a/squashfs-tools/mksquashfs.c b/squashfs-tools/mksquashfs.c
-index 86f82bb..5370ecf 100644
---- a/squashfs-tools/mksquashfs.c
-+++ b/squashfs-tools/mksquashfs.c
-@@ -304,7 +304,7 @@ void restorefs();
- struct dir_info *scan1_opendir(char *pathname, char *subpath, int depth);
- void write_filesystem_tables(struct squashfs_super_block *sBlk, int nopad);
- unsigned short get_checksum_mem(char *buff, int bytes);
--int get_physical_memory();
-+void check_usable_phys_mem(int total_mem);
-
-
- void prep_exit()
-@@ -4053,11 +4053,7 @@ void initialise_threads(int readq, int fragq, int bwriteq, int fwriteq,
- BAD_ERROR("Queue sizes rediculously too large\n");
- total_mem += fwriteq;
-
-- if(total_mem > get_physical_memory()) {
-- ERROR("Total queue sizes larger than physical memory.\n");
-- ERROR("Mksquashfs will exhaust physical memory and thrash.\n");
-- BAD_ERROR("Queues too large\n");
-- }
-+ check_usable_phys_mem(total_mem);
-
- /*
- * convert from queue size in Mbytes to queue size in
-@@ -4879,6 +4875,72 @@ int get_physical_memory()
- }
-
-
-+void check_usable_phys_mem(int total_mem)
-+{
-+ /*
-+ * We want to allow users to use as much of their physical
-+ * memory as they wish. However, for practical reasons there are
-+ * limits which need to be imposed, to protect users from themselves
-+ * and to prevent people from using Mksquashfs as a DOS attack by using
-+ * all physical memory. Mksquashfs uses memory to cache data from disk
-+ * to optimise performance. It is pointless to ask it to use more
-+ * than 75% of physical memory, as this causes thrashing and it is thus
-+ * self-defeating.
-+ */
-+ int mem = get_physical_memory();
-+
-+ mem = (mem >> 1) + (mem >> 2); /* 75% */
-+
-+ if(total_mem > mem) {
-+ ERROR("Total memory requested is more than 75%% of physical "
-+ "memory.\n");
-+ ERROR("Mksquashfs uses memory to cache data from disk to "
-+ "optimise performance.\n");
-+ ERROR("It is pointless to ask it to use more than this amount "
-+ "of memory, as this\n");
-+ ERROR("causes thrashing and it is thus self-defeating.\n");
-+ BAD_ERROR("Requested memory size too large\n");
-+ }
-+
-+ if(sizeof(void *) == 4 && total_mem > 2048) {
-+ /*
-+ * If we're running on a kernel with PAE or on a 64-bit kernel,
-+ * then the 75% physical memory limit can still easily exceed
-+ * the addressable memory by this process.
-+ *
-+ * Due to the typical kernel/user-space split (1GB/3GB, or
-+ * 2GB/2GB), we have to conservatively assume the 32-bit
-+ * processes can only address 2-3GB. So refuse if the user
-+ * tries to allocate more than 2GB.
-+ */
-+ ERROR("Total memory requested may exceed maximum "
-+ "addressable memory by this process\n");
-+ BAD_ERROR("Requested memory size too large\n");
-+ }
-+}
-+
-+
-+int get_default_phys_mem()
-+{
-+ int mem = get_physical_memory() / SQUASHFS_TAKE;
-+
-+ if(sizeof(void *) == 4 && mem > 640) {
-+ /*
-+ * If we're running on a kernel with PAE or on a 64-bit kernel,
-+ * the default memory usage can exceed the addressable
-+ * memory by this process.
-+ * Due to the typical kernel/user-space split (1GB/3GB, or
-+ * 2GB/2GB), we have to conservatively assume the 32-bit
-+ * processes can only address 2-3GB. So limit the default
-+ * usage to 640M, which gives room for other data.
-+ */
-+ mem = 640;
-+ }
-+
-+ return mem;
-+}
-+
-+
- void calculate_queue_sizes(int mem, int *readq, int *fragq, int *bwriteq,
- int *fwriteq)
- {
-@@ -4890,7 +4952,7 @@ void calculate_queue_sizes(int mem, int *readq, int *fragq, int *bwriteq,
-
-
- #define VERSION() \
-- printf("mksquashfs version 4.3 (2014/05/12)\n");\
-+ printf("mksquashfs version 4.3-git (2014/06/09)\n");\
- printf("copyright (C) 2014 Phillip Lougher "\
- "<phillip@squashfs.org.uk>\n\n"); \
- printf("This program is free software; you can redistribute it and/or"\
-@@ -4918,7 +4980,7 @@ int main(int argc, char *argv[])
- int fragq;
- int bwriteq;
- int fwriteq;
-- int total_mem = get_physical_memory() / SQUASHFS_TAKE;
-+ int total_mem = get_default_phys_mem();
- int progress = TRUE;
- int force_progress = FALSE;
- struct file_buffer **fragment = NULL;